Population geography progress and prospect 9780415616119, 0415616115, 9780415616126, 0415616123, 9780709940456, 0709940459, 9781315886633, 1315886634

Table of contents :
Content: 1. Theory and methodology in population geography 2. The British and United States' census of population 3. Fertility patterns in the modern world 4. Mortality patterns in the modern world 5. Governmnet population policies 6. International migration: a spatial theoretical approach 7. Internal migration in the Third World 8. Counterurbanisation 9. Migration and intra-urban mobility 10. Population modelling

Citation preview

ROUTLEDGE

Population Geography: Progress & Prospect

Edited by Michael Pacione

REVIVALS

Routledge Revivals

P op u lation G eography: P rogress and P rosp ect

First p u b lish e d in 1 9 8 6 , this book presents a co m p reh ensiv e overview of th e c o n te m p o ra ry state o f k n o w le d g e in the field o f p o p u la tio n g eo g rap h y . It discusses th e c o n tem p o rary state o f th e art a nd surveys new research d e v e lo p m e n ts and new th i n k i n g in th e m ajo r b ranches of th e subject. It th ereb y provides an in tro d u c to ry g u id e to c o n tem p o rary trend s an d forms a reference p o in t for fu tu re d e v e lo p m e n t in the s u b ­ ject.

T his page intentionally left blank

P op u latio n G eography: P rogress and P ro sp ect

E d ite d by

Michael Pacione

¡3

Routledge

^ ft m ,/ Taylor &Francis Group

First pub lish ed in 1986 by C room H elm T h is edition first pu blished in 2011 by R o utle dg e 2 Park Square, Milton Park, A b in g d o n , O xo n, 0 X 1 4 4 R N Sim ultaneously published in the USA and C anada by R o utled ge 2 70 Madison A venue, N ew Y o rk, N Y 10016 R out ledge is an im print o f the T aylor & Francis Group, an inform a business

© 198 6 Michael Pacione All rig hts reserved. N o part of this book may be reprinted or reproduced or utilised in any form or by any electronic, m echanical, or o th e r means, now k no w n or hereafter invented, inclu ding pho to cop yin g and recording, or in any inform ation storage or retrieval system, w ith o u t perm ission in w ritin g from the publishers. P u b l i s h e r ’s N o t e T h e p ub lishe r has g on e to g reat le n g th s to ensure the q u ality o f this rep rin t b u t points o u t th at some im perfections in the original copies may be apparent. Disclaimer

T h e pu blish er has m ade every effort to trace c o p y rig h t holders and welcomes correspondence from those they have been unable to contact. A Library of C ongress record exists u n d e r LC C on tro l N u m b e r : 8 6 0 0 6 2 1 0

ISBN 13: 9 7 8 - 0 - 4 1 5 - 6 1 6 1 1 - 9 (hbk) ISBN 13: 9 7 8 - 0 - 4 1 5 - 6 1 6 1 2 - 6 (pbk)

Population Geography: Progress & Prospect Edited by MICHAEL PACIONE

V

CROOM HELM London • Sydney • Dover, New Hampshire

© 1 9 8 6 Michael Pacione Croom Helm Ltd, Provident House, Burrell Row, Beckenham, Kent BR3 1AT Croom Helm Australia Pty Ltd, Suite 4, 6th Floor, 64-76 Kippax Street, Surry Hills, NSW 2010, Australia British Library Cataloguing in Publication Data Population geography: progress and prospect. 1. Population geography I. Pacione, Michael 304.6 HB1951 ISBN 0-7099-4045-9

Croom Helm, 51 Washington Street, Dover, New Hampshire 03820, USA Library of Congress Cataloging in Publication Data Population geography. (Croom Helm Progress in geography series) Includes index. 1. Population geography. 2. Census. 3. Fertility, Human. 4. Mortality. 5. Population policy. I. Pacione, Michael. II. Series. HB1951.P653 1986 304.6 86-6210 ISBN 0-7099-4045-9

Printed and bound in Great Britain by Biddles Ltd, Guildford and King's Lynn

CONTENTS

List of T ab les List o f F ig u re s P reface INTRODUCTION 1.

THEORY AND METHODOLOGY IN POPULATION GEOGRAPHY R .I . Woods

2.

THE BRITISH AND UNITED STATES* CENSUSES OF POPULATION J . C . D ew dney a n d D. R hind

3.

FERTILITY PATTERNS IN THE MODERN WORLD J . C ow ard

4.

MORTALITY PATTERNS IN THE MODERN WORLD P .H . C u rso n

5.

GOVERNMENT POPULATION POLICIES I. Thom as

6.

INTERNATIONAL MIGRATION: A SPATIAL THEORETICAL APPROACH J . Salt

7.

INTERNAL MIGRATION IN THE THIRD WORLD J . G u g ler

8.

COUNTERURBANISATION A .J . F ield in g

9.

10.

MIGRATION AND INTRA-URBAN MOBILITY M. C adw allad er POPULATION MODELLING P. R ees

257

284

N otes on C o n trib u to rs

317

Ind ex

318

T A B L E S AND F IG U R E S

Tables 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 4.1 4.2 5.1 5.2 5.3

F e rtility ra te s b y reg io n fo r th e e a rly 1980s............ R elationships betw een th e to ta l fe rtility ra te and v a rio u s dem ographic an d socio-economic v a r ia b le s .. G overnm ent p e rc e p tio n s of fe rtility level by a re a , num ber of c o u n trie s an d p e rc e n ta g e d istrib u tio n of p o p u latio n ................................................................................ V ariations in family size b y social c la ss in 1951 and 1971, d u ra tio n of m arriage 20-24 y e a rs (s ta n d a rd is e d fo r age at m a rria g e ).................................... D istric ts with p a rtic u la rly high o r low age s ta n ­ d a rd ise d fe rtility in 1981 by major in flu en cin g fa c to rs ............................................................................................ R elationship betw een age sta n d a rd ise d fe rtility and v ario u s dem ographic and socio-economic v ariab les 1981.............................................................................. R elationships betw een m arital fe rtility and h y p o th esised ex p la n a to ry v a ria b le s, Scotland 1981.................................................................................................. V ariations in family size in N o rth ern Ire la n d by a rea and relig ion , 1983 (e v e r-m a rrie d women aged 45 -5 9).................................................................................... S tan d ard ised m ortality ratio s b y social c la ss, males aged 15-64 y e a r s , E ngland a n d Wales 1921-72............................................................................................ In fant d eath ra te s by social c la s s , England and Wales, av erag e 1979-81........................................................... In q u iries into population in itia te d by th e g o v e rn ­ ments of Developed n a tio n s, 1961-72................................ C hanges in th e commitment to family plan n in g program m es among low and middle income n a tio n s, 1972-82............................................................................................ Family plan ning in E ngland and Wales (a ) m ethods of co ntracep tion e v e r used by women with a legitim ate b ir th , 1967/8 to 1975; ( b ) u se of th e

63 66 69 73 78 82 87 91 101 104 133 135

5.4

5.5 5.6 6.1 6.2 7.1 8.1 8.2 8.3 10.1 10.2 10.3 10.4 10.5 10.6

family p lan n in g s e rv ic e s , 1970 an d 1975 (e v e rm arried women u n d e r 4 1 ).................................................. A bortion in E ngland and Wales (a ) legally in d uced ab o rtio n s ( r e s id e n ts ) , 1969-83; (b ) legally in d u ced ab o rtio n ra te s ( p e r th o u sa n d fo r women aged 15-49) by S ta n d a rd R egions, 1968-73............... C hanges of th e volume of UK im m igration b y a rea of o rig in , 1966-81................................................................. A classification of in te rn a l m igration and re d is trib u tiv e program m es w ith selected exam ples from A fric a ................................................................................ U nited Kingdom: lo n g -term work p erm its issu ed 1981-83 .................................................................................. U nited Kingdom; lo n g -term w ork p erm its to p ro fe s ­ sional an d m anagerial w o rk ers 1983................................ D em ographic c h a ra c te ris tic s an d income of major T h ird World c o u n trie s ........................................................... A nnual n et m igration ra te s p e r th o u sa n d population fo r US non-m etropolitan a re a s 1960-70 and 1970-75. Ratio of m etropolitan to n on-m etropolitan p o p u l­ ation grow th ra te s in th e US 1950-80............................ Net in te rn a l m igration ra te s p e rc e n t population for major reg io n s in F ra n c e , 1954-62 an d 1975-82........... Sixteen life h isto ry ty p e s ................................................... Nine life h isto ry ty p e s ......................................................... An estim ate of th e num ber of p e rso n s in th e OPCS longitudinal stu d y in a classification u sin g nine life h isto ry ty p e s ................................................................... Population accou nts: s tr u c tu r e and exam p les........... A dem ographic m atrix co n n ectin g o p en ing and closing population sto ck s in a time in te rv a l u sin g tra n sitio n d a ta ......................................................................... A dem ographic m atrix co n necting op en in g and closing population sto ck s in a time in te rv a l u sin g movement d a ta .........................................................................

140

142 143 154 178 179 196 230 238 238 287 288 290 296 302 304

F igures 1.1 1.2 2.1 3.1 3.2 3.3 3.4

A diagram atic summary of T re w a rth a 's system fo r population g e o g ra p h y ........................................................... A th eo retical window.............................................................. US cen su s map and eq u iv alen t GBF/DIME file ............ Regional v ariatio n s in family size in England and Wales; 1951, 1961, and 1971.............................................. D istricts with p a rtic u la rly high o r p a rtic u la rly low age sta n d a rd ise d fe rtility , 1981.............................. V ariations in Coale's in d ices of fe rtility , Scotland 1981........................................................................... C hanges in th e in dices of fe rtility 1971-81 in th e Republic of Ire la n d ...............................................................

15 19 51 72 76 85 89

4.1

S ta n d a rd ise d m ortality ra te s b y social c la ss fo r age g ro u p s an d selected cau se of d e a th , E ngland an d Wales, 1970-72................................................................. 4.2 S ta n d a rd ise d m ortality ra tio s , A u stralian m ales, occupational g r o u p s ................................................................. 4.3 In fan t an d p e rin a ta l m ortality b y reg ional health d is tric ts an d social c la s s , E ngland an d Wales, 1979-81.......................................................................................... 4.4 A g e-ad ju sted d eath ra te s b y se le c te d cau ses by ra c e , USA, 1950-77................................................................. 4.5 Major c au ses of d e a th , D eveloped an d D eveloping c o u n trie s, c.1 9 8 0 ..................................................................... 4.6 S ta n d a rd ise d m ortality ra tio s b y u rb a n an d nonu rb a n a re a s , New Z ealand, 1964-67................................ 4.7 Life ex p ectan cy at b ir th c.1 9 8 0 ........................................ 4.8 In fan t m ortality ra te s c.1 9 8 0 ............................................ 4.9 Male life ex p ectan cy a t b ir th , reg io n s o f w estern an d n o rth e rn E u ro p e, 1969-77.......................................... 4.10 D istrib utio n of diastolic blood p r e s s u r e , chol­ estero l and o besity ra te s , Sydney M etropolitan A rea, 1970-75............................................................................. 5.1 World map of governm ent family p la n n in g and pop­ ulation reduction program m es, 1978.................................. 5.2 Schematic lin k s betw een re se a rc h and governm ent policy and program m es........................................................... 5.3 National population grow th 1970-82, by continent and World Bank income g ro u p s .......................................... 5.4 T ren d of c ru d e b irth ra te in India 1962-82 and th e ta rg e ts in su ccessiv e fiv e -y e a r developm ent p la n s .. 6.1 World refu g ee map..................................................................... 6.2 A global refu g ee sy stem ........................................................ 8.1 US annual n et m igration ra te s p e r th o u san d pop­ ulation 1960-70 and 1970-75 by settlem ent size (SMSA) c a te g o ry ....................................................................... 8.2 T re n d in US regional annual n et m igration ra te s p e r th o u san d population 1960-70 to 1970-75................. 8.3 Net m igration b y ty p e of region Jap an 1955-82........... 8.4 F ra n c e , annual n e t m igration r a te s p e r th o u sa n d population 1954-82 by settlem en t size (r u r a l commune an d u n ite s u rb a in e s) c a te g o ry ....................... 10.1 Life h isto rie s in an ideal d ata s e t ................................ 10.2 Examples of s ta te to s ta te tr a n s f e r s employed in population models..................................................................... 10.3 Age-time o b serv atio n p la n s ..................................................

100 102 103 107 109 Ill 114 115 116 122 136 139 141 149 182 186 228 231 236 237 286 291 298

To C h ris tin e , M ichael Jo h n a n d Emma V ictoria

PREFACE

The stu d y of population re p re s e n ts an in te g ra l com ponent of human g eo g rap h y , y e t only since th e early 1950s h as p o p u l­ ation geography em erged from th e academ ic shadow s to become an acknow ledged su b -b ra n c h of th e d iscip lin e. While po p u l­ ation is also a focus of in v estig a tio n fo r o th e r s u b je c ts , such as dem ography, economics and sociology, population geography is ch a ra c te rise d by its p a rtic u la r p e rs p e c tiv e on spatial asp ects of population and on th e lin k s betw een population and th e environm ent. C ontem porary in v e stig a tio n s in population geography focus on th e th re e major dem ographic facto rs of fe rtility , m ortality and m igration. R ecent d evelop­ ments in population g e o g rap h y have m irro red tr e n d s in th e discipline as a whole. T hese have in clu d ed a sh ift of em phasis from d escrip tio n of p a tte rn s of population d is trib u tio n and comparison p e r s e , tow ards an em phasis on th e p ro c e sse s u n d erly in g o b serv ed p a tte rn s . T h e re h as also been a re -o rd e rin g of re s e a rc h em phasis among th e th re e main them es with g re a te r atten tio n d evoted to population mobility and m igration stu d ie s. T his re fle c ts b oth th e im portant social an d economic im plications of population movem ents, an d th e avail­ ability of spatially d isa g g re g a te d d a ta . T h ese ch an g es have been accompanied by developm ent of an applied o r problem o riented p e rs p e c tiv e , as dem o n strated by p o licy -re le v a n t in v estig atio n s in th e fields of settlem ent an d economic p la n ­ nin g and in the evaluation of th e e ffe c ts of population policies. Modern population g eo g rap h y is a m u lti-faceted s u b ­ ject area which see k s to blend tra d itio n a l d e sc rip tio n s of fe rtility , m ortality and m igration p a tte rn s with a n a ly se s o f th e dynamic p ro cesses u n d e rly in g th e se p a tte r n s . T his collection of o riginal e ssa y s is d esig n e d to en cap ­ sulate th e major them es and re c e n t developm ents in a num ber of areas of c e n tra l im portance in population g e o g rap h y . T he volume is a d ire c t re sp o n se to th e need fo r a te x t which review s th e p ro g re ss an d c u rre n t s ta te o f th e su b jec t an d which p ro v id es a re fe re n c e p oint fo r fu tu re developm ents in population geo g rap h y . Michael Pacione U niv ersity o f S tra th c ly d e Glasgow

T his page intentionally left blank

IN T R O D U C TIO N

The p lu ra listic n a tu re of population g e o g ra p h y , with its s tro n g links to dem ography an d population s tu d ie s , is acknow ledged in C h a p te r 1 in which Bob Woods review s re c e n t developm ents in th e th e o ry and m ethodology of th e su b je c t. The fundam ental q u e stio n of th e d efin itio n of population geo g rap h y is co n sid ered and a d istin ctio n is draw n betw een bro ad definitions (su c h as th a t em ployed b y T re w a rth a ) and narro w er statem en ts w hich seek to c o n c e n tra te a tte n tio n on dem ographic g eo g rap h y (ie . th e stu d y o f v a ria tio n s in popu­ lation dynam ics via an aly sis of m o rtality , fe rtility and m igration com ponents a t v a rio u s s c a le s .) C ontem porary popu­ lation g eo g rap h y accommodates r e s e a r c h e rs e sp o u sin g both dem ographic as well as tra d itio n a l g eo g rap h ic p e rs p e c tiv e s . While su ch p lu ra lity may prom ote p ro g re s s in th e su b je c t it can also be a rg u e d th a t th e failu re to d efine a p re c ise a re a of in te re s t and e x p e rtise h as c o n trib u te d to th e limited in fluence of population g eo g rap h y in th e g en eral field o f population re s e a rc h . A ttention th e n tu r n s to th e o re tic a l co n sid eratio n s. The p u rp o se of th e o ry and th e re la te d q u e stio n o f how a th e o ry can be v alid ated a re su b ject to d etailed exam ination. The d iscu ssio n th e n exam ines th e d iffe re n t lev els a t which th e o rie s may be c o n s tru c te d . T h re e d is tin c t scales a re rec o g ­ n ise d . Micro th e o ry , which seek s to u n d e rs ta n d individual b eh av io u r, is illu s tra te d w ith re fe re n c e to th e stu d y of m arriage p ra c tic e s w ithin an environm ent o f c o n stra in ed choice. M iddle-range th e o ry which is co n ce rn ed with th e c h a ra c te ris tic s of g ro u p s of people is th e most commonly employed level of co n cep tu alisatio n . Work a t th is scale is exem plified by E a ste rlin 's attem p ts to combine economic and sociological th e o rie s of fe rtility . G rand th e o ry is d ire c te d at long term social, economic an d dem ographic c h an g e an d is b e st illu s tra te d b y dem ographic tra n s itio n th e o ry . T he b a sis of a flexible th e o ry of dem ographic b e h a v io u r b a se d on th e in te ra c tio n of a v a rie ty of causal fa c to rs is s u g g e s te d . Five p rin cip al methodologies fo r population g eo g rap h y a re th e n co n sid ered . Empiricism h as been th e dom inant approach to 1

IN TRODUCTION

p a tte rn identification and modelling with significant co n tri­ butions being made in fields such as m ultiregional demo­ graphic accounting, and autom ated c a rto g ra p h y . When attem pting to estab lish causal relationships some form of positivism has normally been invoked. Though of continued relevance in population g eo g rap h y , th e lim itations of positivism have led to th e consideration of altern ativ e approaches, with for exam ple, a behavioural p ersp ectiv e being of p a rtic u la r u tility in migration stu d ie s. D espite several problems (such as th e non-replicability of su rv e y re su lts) the behavioural and hum anistic approaches can improve u n d e r­ standing of th e forces o p eratin g to produce observed popu­ lation p a tte rn s . The s tru c tu ra l p ersp ectiv e views human behaviour as conditioned by the dominant mode of p ro d u ctio n , with each mode having its own laws of population. The poten­ tial and problems of each of th ese methodologies a re a ssessed . Two fundam ental issu e s fo r population geography re fe r to the definition of the subject a re a , and how to increase the influence of th e geographical component within population stu d ies. It is su g g ested th a t th e answ er to both questions lies in g re a te r specificity with concentration on key topics, g re a te r use of demographic tech n iq u es, and the development of an applied o r problem -oriented population geography. Finally, th re e p a rtic u la r are a s in which g eo g rap h ers can make a significant contribution are id en tified . F irst, the develop­ ment of a com prehensive th eo ry of m igration. Second, study of spatial v ariations in demographic s tru c tu re between cultural regions and th e ir historical developm ent, th ird , fu rth e r development of geographical d ata b ases and application of forecasting methods to contem porary issu e s. The national census generally re p re s e n ts the most com­ prehensive and up to date set of inform ation available on the dem ographic, economic and social c h a ra c teristic s of a popu­ lation. As such it is a prime data source for re se a rc h e rs. In C hapter 2 John Dewdney and David Rhind seek to introduce potential u se rs to th e c h a ra c teristic s of th ese data se ts by describing the n atu re of th e population censuses in B ritain and th e United S tates. The B ritish census is one of the longest series of decennial population d ata in the w orld. The origin and development of the modern census s tru c tu re is discussed and th e major innovations ( e .g . adoption of the household as the basic u n it of enum eration) and difficulties (e .g . in te r-c e n sa l boun d ary changes) id en tified . Issues related to the collection and p ro cessin g of the data a re th en ad d ressed inclu d in g , for exam ple, the legal b a sis of the cen su s, confidentiality c o n stra in ts, th e enum eration d istric t base and th e role of th e enum erator, cen su s layout, and the means of p rocessing th e 1000 million pieces of information on nearly 20 million household schedules. The v arie ty of forms of output covering d ifferen t geographic scales is d esc rib e d . These ran g e from p ublished volumes (including county, 2

IN T R O D U C T IO N

reg io n al, new tow n, an d national re p o r ts to g e th e r w ith key s ta tis tic s fo r local a u th o rity an d u rb a n a re a s ) to th e u n p u b ­ lished small a rea s ta tis tic s which con tain almost all cla ssi­ fications an d c ro s s -ta b u la tio n s likely to b e of relev an ce to re s e a rc h e rs . A nalysis of th is d a ta h a s been facilitated by com puter p ack ag es su ch a s SASPAC. A sim ilar o rg an isatio n al fram ework is em ployed to exam ine th e p ro p e rtie s a n d p o ten tial of th e U nited S ta te s' c e n s u s. The ra p id g row th of inform ation contained in th e c e n su s re q u ire d th e in tro d u c tio n of adm inis­ tra tiv e an d tech n ical in n o v atio n s in m ethods of collection and p ro c e ssin g . T hese have in clu d ed th e in tro d u c tio n of FOSDIC (film optical se n sin g device fo r in p u t to c o m p u te rs), th e use of sam pling te c h n iq u e s in d a ta collection, an d th e d istrib u tio n and collection of forms by pub lic mail. A d e tailed exam ination of th e s tr u c tu r e of th e 1980 c e n su s is p r e s e n te d , an d th e problem s of i t s p ro se c u tio n d is c u s s e d . P a rtic u la r a tte n tio n is afforded to th e sp atial dim ension of th e US ce n su s an d th e function of m aps, g eo g rap h ic b ase file s /d u a l in d e p e n d e n t map encoding, an d s ta te m aster re fe re n c e files e x p la in ed . T hese th re e elem ents o ffe r th e p o ten tial fo r autom ated tab u latio n of re s u lts fo r an almost in fin ite v a rie ty of g eo graphical b ase s ( e .g . SMSAs, school d is tr ic ts , c e n su s t r a c t s , enum eration d is tric ts and b lo c k s). T he co n ten t of th e US c e n su s is con­ sid ered with p e rh a p s th e g re a te s t c o n tra s t with B ritain being the inclusion of d ire c t q u e stio n s on incom e, p ro p e rty v alu e/ r e n t, an d cost of u tilitie s and fu el. For r e s e a rc h e rs a sig n ifi­ cant d ifferen ce is in th e cost of o b tain in g d a ta , with th e US ce n su s re g a rd e d as pub lic domain. F in ally, fu tu re d ev elop­ ments a re id e n tifie d a n d major c o n tra s ts an d com parisons draw n betw een B ritain and th e United S ta te s. The im portance of fe rtility s tu d ie s in b o th academic ( e .g . to explain population s tr u c tu r e s ) an d p ra c tic a l term s ( e .g . p re d ic tin g dem and for se rv ic e s) h a s not been reflec ted in th e volume of work dev o ted to th is a sp e ct of population geo g rap h y . In C h a p te r 3 John Coward se e k s to re d re s s th is im balance b y exam ining fe rtility p a tte r n s in th e m odern world at a v a rie ty of g eo g rap h ic scales. At th e global level fe rtility p a tte rn s a re c h a ra c te ris e d b y sig n ifican t v a ria tio n s betw een re g io n s, and in th e v a ria b le s in flu en cin g su ch d is trib u tio n s . Factors su g g e ste d to explain th e re c e n t in cidence of low f e r ­ tility ra te s include th e diffu sio n of "m odernisation" to some T h ird World c o u n trie s , with a key v ariab le b ein g th e ch a n g ­ ing position of women in so c ie ty , a s re fle c te d in b e tte r levels of ed u catio n , in c re a se d s ta tu s an d s e c u r ity , an d h ig h e r p ro ­ po rtio n s of economically activ e fem ales. O th e r causal fa c to rs are th e e ffe c ts of family p la n n in g schem es, c u ltu ra l a n d r e ­ ligious b e lie fs, an d governm ent policy a n d a ttitu d e s . A ttention is th e n focussed on th e in tra -n a tio n a l scale an d on an an aly­ sis of re c e n t fe rtility p a tte r n s w ithin th e B ritish Isle s. Significant them es id en tified fo r E ngland a n d Wales a re th e decline in regional fe rtility d iffe re n tia ls o v e r th is c e n tu r y , 3

IN T R O D U C T IO N

b u t th e con tin u ed e x isten ce of fe rtility d iffe re n c e s a t th e local level. Such fin d in g s clearly u n d e rlin e th e im portance o f scale of an aly sis in g eo g rap h ic in v e s tig a tio n s . T he p rin cip a l fa c to rs co n trib u tin g to th e regional p a tte r n s w ere id en tified as a decline in social c la s s -b a s e d d iffe re n tia ls in fe r tility , a n d th e regional co n v erg en ce of key v a ria b le s in flu en cin g fe rtility (su c h as female p a rtic ip a tio n in th e la b o u r fo rce , a n d th e sp re a d of new c u ltu ra l v a lu e s an d n o rm s). A nalysis o f th e p ro n o u n ced v a ria tio n s in fe rtility a t th e d is tric t level examined th e c o n trib u tio n of each of th e th re e c o n stitu e n ts of fe rtility (m arital f e rtility , p ro p o rtio n s m arrie d , an d e x tr a ­ m arital fe rtility ) to th e o b se rv e d p a tte r n s . O verall it is con­ cluded th a t while c e rta in dem ographic and socio-economic facto rs c o n trib u te to v a ria tio n s in a g e -s ta n d a rd is e d fe rtility th e level of ex p lan atio n is fa r from com plete and continued search for additional v a ria b le s is e s se n tia l. Similar a n a ly ses a re p re s e n te d fo r th e o th e r c o u n trie s of B rita in , a n d th e Republic of Ire la n d . In th e la tte r , a n a ly sis of d a ta fo r th e p erio d 1971-1981 at th e co u n ty level id en tified th e dom inant tre n d a s an extrem ely h ig h (25%) decline in m arital fe rtility . Possible ex p la n a to ry fa c to rs in clu d e a decline in a g ric u ltu re , th e grow th of an u rb a n -b a s e d m id d le-class, r e tu r n m igration from B rita in , in c re a se d employment o p p o rtu n itie s fo r m arried women, and th e in c re a s in g s tr e n g th of feminism and risin g secularism among th e y o u n g . F u r th e r p ro g re s s in u n d e r­ sta n d in g fe rtility tr e n d s re q u ire s co n tin u ed an aly sis o f sp atial fe rtility p a tte rn s b o th to id e n tify ad d itio nal fe rtility -re la te d v a ria b le s, and to a s s e s s th e role of g e n e ra l models o f fe rtility ch an g e. Methodological q u e stio n s of p a rtic u la r im portance concern th e n a tu re and availability of d ata and th e influence of scale on em pirical fin d in g s. In C h a p te r 4 P e te r C u rso n illu s tr a te s th e p o tentially significan t role of m ortality s tu d ie s w ithin a m odern p ro c e s s o rien ted population g e o g ra p h y . It is o b se rv e d th a t while medical g eo g rap h y h as c o n trib u te d to th e sp atial an a ly sis o f m ortality le ss co n sid eratio n h a s b een given to th e q u e stio n of d iffe re n tia l m ortality a ris in g from v a ria tio n s in social c la ss, occup atio n , e th n ic ity , ra c e , age and se x . Examination o f th e social in eq u ality of d e a th s u p p o rts th e e x iste n c e o f an in v e rs e relatio n sh ip betw een m ortality and social c la ss, (w hich is its e lf a summary m easure of a ra n g e of fa c to rs in clu d in g living an d w orking co n d itio n s, n u tritio n le v e ls, m aternal s ta tu s and access to h ealth c a re fa c ilitie s). S ig n ifica n tly , evidence from England and Wales b ased on s ta n d a rd is e d mor­ tality ra tio s for d iffe re n t social g ro u p s s u g g e s ts th a t th e class g ra d ie n t h as ste e p e n e d o v e r th e la st half c e n tu r y , a fact which clearly q u e stio n s th e d is trib u tiv e im pact o f th e h ealth care im provem ents of th e la st e ig h ty y e a r s . Such c la ss-b a se d d isp a ritie s a re of ev en g re a te r m agnitude in th e T h ird World. Significant d iffe re n c es in m ortality p a tte r n s are also found betw een racial and eth n ic m inorities a n d th e 4

IN T R O D U C T IO N

majority population in D eveloped C o u n tries w ith , in some c a se s, th e in cidence of childhood m ortality com parable to ra te s in th e T h ird World s ta te s . At a g e n e ra l level a c le a r d istin c ­ tion in major cause of d e a th e x is ts betw een w estern d e g e n e r­ ative d ise a se s (su c h as h e a rt d isease) an d th e p a ra s itic and infectio u s d iseases ( e .g . g a s tro e n te ritis a n d tu b e rc u lo sis) which dom inate m ortality p a tte r n s in th e D eveloping World. The sp atial p a tte rn in g of m ortality h a s a ttra c te d most geo­ graphical a tte n tio n and exam ples of th is re s e a rc h a re p ro v id ed at th e in te rn a tio n a l, regional an d in tr a - u r b a n sc a le s. While th e m apping of m ortality d is trib u tio n s can d e sc rib e p a rtic u la r environm ents of r is k , in d ic a te p o ssib le lin es of epidemiologic en q u iry , and su g g e st m odifications to h e a lth c are program m es causativ e ex planation r e p re s e n ts a more elu siv e goal. Some p ro g re s s h as been made in id e n tify in g ris k fa c to rs in th e n atu ral and social en v iro n m en ts which c o n trib u te to p rem atu re d eath . T hese gen erally inclu d e clim ate, a ir and w ater pol­ lution and hou sin g co n d itio n s, while in a T h ird World c o n te x t, the role of environm ental fa c to rs , lan d u se p ra c tic e s an d th e effe c ts of th e developm ent p ro c e ss have all been re la te d to disease h a z a rd . The c e n tra l problem , h o w ev er, rem ains th a t of e sta b lish in g a causal lin k , (as opposed to a sta tistic a l re la tio n sh ip ), and it may be th a t "th e scien tific dem onstration of cau sality in g eo g rap h ic re s e a rc h rem ains an illu so ry and unobtainable goal". It is su g g e s te d th a t lo n g itu d in al and cohort stu d ie s and re c o n stru c tio n o f p e rso n a l h isto rie s may offer g re a te r prom ise th a n c u r r e n t re sid e n c e -b a se d stu d ie s o f m ortality. It is also n e c e ssa ry to in c o rp o ra te a g r e a te r ran g e of p ossible fa c to rs ( e .g . biochem ical o r p h y sio lerg ic in flu ­ ences) in to th e a n a ly sis. It is concluded th a t more so p h isti­ cated methodologies which reco g n ise th e tem poral as well as spatial dim ensions of d ise a se , and in v e stig a tio n s a t more detailed le v e ls, c o n c e n tra tin g on p a rtic u la r population g ro u p s are re q u ire d if we a re to ap p ro ach th e objective o f u n d e r­ sta n d in g th e p ro c e sse s which lead to sp a tia l v a ria tio n s in m ortality. All governm ents en act policies w hich, e ith e r d ire c tly o r in d ire c tly , affect th e n a tu ra l grow th a n d d is trib u tio n of th e ir pop u latio n s. Population policies can seek to achieve a num ber of o b jectiv es, ra n g in g from u rb a n d eco n gestion to national developm ent. The s tra te g ie s selected re fle c t th e view s of governm ent an d in te rn a l p re s s u r e g ro u p s as well a s th o se o f in te rn a tio n a l ag encies an d re s e a r c h e r s . In C h a p te r 5 Ian Thomas exam ines th e re la tio n sh ip b etw een population re se a rc h and governm ent p o licy , an d ex p licitly c o n sid e rs th e c o n tri­ b ution of a g eographical ap p ro ach to th e an aly sis o f th e com ponents of population policy. It is a rg u e d th a t while o th e r disciplines also exam ine th e fa c to rs asso ciated with population dynam ics g eo g rap h y h as a p a rtic u la r re sp o n sib ility to explain regional v a ria tio n s in th e o p eratio n a n d outcome o f th e se fo rc e s. A ttention is th e n focussed on th e n a tu re an d o rig in of 5

INTRODUCTION

population policy in th e United Kingdom w here concern in the in te r-w a r period o v er th e uneven regional incidence of u n ­ employment and low levels of fe rtility was rep laced , in the po st-w ar e ra , by policies with an ti-g ro w th tendencies ( e .g . family planning programmes and immigration c o n tro ls). In assessin g th e co ntribution of geographical stu d ies to the formulation of population policy th re e areas of re se a rc h are considered. The firs t re fe rs to policies designed to affect the ra te of population grow th and in th is area th e geographical in pu t is significantly less th an th at of the o th e r social sciences. Potential areas for geographic analysis include the diffusion and utilisation of family plan n in g , the influence of sp atial-cu ltu ral variations in th e acceptibility of policies, regional and social differen tials in m ortality, and th e policy implications of concentrations of elderly o r ethnic populations. Policies designed to affect population d istrib u tio n and re d is­ trib u tio n have been more d irectly influenced by geographic investigation in term s of both migration th eo ry and empirical stud ies of migration m otives, m igrant c h a ra c te ristic s, and the impact on origins and d estin atio n s. T his is illu stra te d with reference to geographical re se a rc h into African populations. The th ird main research area considered com prises geographic studies which affect policy in d ire c tly . T hese include regional studies of population as well as them atic investigations of housing and tra n s p o rt issu e s and methodological advances in data collection and analy sis. It is observed th a t, over recent decades, governm ents in both th e Developed and Developing World have displayed in creasin g in te re s t in the stu d y of population dynamics in o rd e r to acquire information on which to base national planning p rio ritie s. T here is also concern over inequalities at regional and u rb an le v e ls, and a general in te re st in the relationship between population d istrib u tio n and social and economic developm ent. Such tre n d s em phasise the relevance and potential of a geographical approach to population policy. Migration is a human activ ity which occurs at all geo­ graphic scales from local to in tern atio n al, and the analysis of migration flows re p re s e n ts a major area of re se a rc h in contem­ porary population g eography. In C h ap ter 6 John Salt examines the contribution of th e spatial approach to the analysis of intern atio n al m igration, co nsidering both vo lu n tary labour and inv o lu n tary refugee movements. Problems relatin g to data and definitional lim itations and th e absence of an em pirically-verified universally applicable model of international migration are considered. An analytical framework is proposed which recognises th a t (a) geographical p a tte rn s of in ternational m igration occur within a system s framework and are related to complex netw orks of in te rac tio n , and (b ) combinations of global and local forces produce spatial migration netw orks which d iffe r in scale and behaviour. The in creased explanatory pow er gained b y the 6

IN T R O D U C T I O N

move from m acro-scale models b ased on social p h y sic s tow ards p ro c e ss-o rie n te d micro an aly tic p e rs p e c tiv e s on m igrant b eh av io u r is also u n d e rlin e d . The n a tu re of political b a r r ie r s to in te rn a tio n a l m igration is th e n d is c u sse d b e fo re th e ch a ra c te ristic s of a s e rie s of m igration n etw o rk s is exam ined. It is em phasised th a t in o rd e r to u n d e rs ta n d th e com plexity of in tern atio n al sy stem s, know ledge of a g g re g a te la b o u r m arket conditions m ust be complemented b y inform ation on th e socio-economic and dem ographic fa c to rs which u n d erlie population m ovem ents. T he phenom enon of r e tu r n m igration has a ttra c te d co n sid erab le in te r e s t in re c e n t y e a rs . To d a te , how ever, re se a rc h h a s c o n c e n tra te d upon th e economic dimen­ sion, and more detailed in v e stig a tio n of th e h e te ro g e n e ity and d iffe rin g m otivations of m ig ran ts is re q u ire d . Specific a tte n ­ tion is th e n affo rd e d to th e m igration of h ig h -le v el m anpower. It is s u g g e ste d th a t v a ria tio n s in th e ty p e of perso n n el involved an d ch an g es in th e n a tu re of flows o v e r time re fle ct governm ent s tra te g ic re q u ire m e n ts an d p o licies, th e n a tu re of economic lin k ag es betw een c o u n trie s , an d th e lab o u r policies of em ployers, p a rtic u la rly m ulti-national com panies. In con­ tra s t to lab o u r m igration th e en fo rced movement of re fu g e e s is an u n d e r-re s e a rc h e d com ponent o f in te rn a tio n a l m igration, with most w ork to d ate fo cu ssin g on th e co n seq u en ces r a th e r th an on achieving th e o re tic a l u n d e rs ta n d in g of th e causal forces. A ttem pts which have been made to concep tu alise th e determ in an ts of re fu g e e flows a re c o n s id e re d , ra n g in g from typological s tr u c tu r e s b a se d on th e c h a ra c te ris tic s of re fu g e e s to an aly ses of th e political fo rces g e n e ra tin g movement. A model of th e global refu g ee system is p re s e n te d a s a p o te n ­ tially u sefu l e x p la n a to ry fram ew ork fo r th e an a ly sis of refu g ee flows. It is em phasised th a t while political fa c to rs generally u n d erlie refu g ee movements th e v a rie d n a tu re of th e re su ltin g flows d efines a cle a r role for g eo g rap h ical a n a ly sis. The spatial ap proach to th e s tu d y of in te rn a tio n a l m igration is c h a ra c te rise d a s b o th em pirical (ie . d a ta d e p e n d a n t) and pragm atic (ie. co n cern ed with re a l w orld p ro b lem s). It is concluded th a t th e major c o n trib u tio n of th e g eographical approach lies in its ab ility to id e n tify v a ria tio n s w ithin and betw een m igration n e tw o rk s, which b o th h ig h lig h ts th e d a n g e r of o v erg en eralisatio n and h elp s d efine th e lim its of any general th e o ry of in te rn a tio n a l m igration. In C h a p te r 7 Josep h G ugler exam ines th e phenom enon of in te rn a l m igration in T h ird World c o u n trie s w here th e p r e ­ dominant c h a ra c te ris tic is population g row th in b o th u rb a n and ru ra l a re a s . Two major m igratory p a tte r n s a re e v id e n t; ru ra l - ru ra l movements ( e .g . in re sp o n se to p r e s s u r e on th e land re s o u rc e , o r due to n a tu ra l d is a s te r s ) , and r u r a l-u r b a n m igration. T he la tte r is th e su b ject of p a rtic u la r a tte n tio n , given th e social, economic an d political problem s p o se d , and the cru cial role of th is m igration p ro c e ss in th e global u rb a n tra n sitio n . T he e ffe c ts of th e in co rp o ratio n o f tra d itio n a l 7

IN T R O D U C T IO N

economies in to th e w orld c ap italist system a re th e n d isc u sse d . T hese inclu d e th e ac c e lera te d grow th of population and an in c re a se d significance of th e u r b a n - r u r a l gap in liv in g s ta n ­ d a rd s . The n a tu re and e x te n t o f th e se d iffe re n c e s, m easure­ ment p ro b lem s, an d th e n e c e ssity of d is a g g re g a tin g d a ta to co n sid er th e position of in d iv id u al m ig ran ts a re d isc u sse d . It is su g g e s te d th a t u rb a n -b ia s on th e p a r t of governm ent decision-m akers is a major cau sal fa c to r w ith r u r a l p e a s a n ts , effectiv ely d e p riv e d of political an d economic re p re s e n ta tio n , re s o rtin g to m igration in an attem pt to im prove th e ir q u ality of life. T he fact th a t th e fundam ental fa c to r u n d e rly in g r u r a lu rb an m igration is economic lead s to exam ination o f th e u rb a n lab o u r m ark et. It is o b se rv e d th a t w h ereas in th e colonial perio d em ployers e x p e rie n c ed h ig h ra te s of la b o u r tu rn o v e r and ab sen teeism , a s economies w ere in c o rp o ra te d in to th e world system la b o u r s h o rta g e s w ere rep la c e d by o v e rs u p p ly , unem ployment an d underem ploym ent. T he dynam ics o f th is radical chan g e a re e x p lo re d . V ariation in th e s tr u c tu r e of u rb a n lab o u r m ark ets also u n d e rlie s two in te rp re ta tio n s of m igrating b e h a v io u r. T he f ir s t p o s tu la te s a random p ro c e ss of lab o u r re c ru itm e n t c h a ra c te rise d as an u rb a n job lo tte ry , in which relativ ely ra p id tu rn o v e r an d h ig h minimum w ages made even an e x te n d e d job se a rc h a w orthw hile s tr a te g y . T his how ever a p p e a rs to have b een an excep tio nal model, ty p ified b y tro p ical A frica in th e p o st-co lo n ial e r a . More commonly, labour recru itm en t is s tr u c tu r e d on th e b a sis of a se t o f segm ented m ark ets w ith access to job o p p o rtu n itie s d ep e n d e n t upon th e m ig ran ts' e d u c a tio n , s e x , a g e , tra in in g and p a tro n ­ ag e . It is em phasised th a t th e flow of m ig ran ts in to cities re p re s e n ts only a fra c tio n of th e p o te n tial m ig ran ts in th e ru ra l r e s e rv o irs . T h ree p rin c ip a l p a tte r n s of m igration are id e n tifie d , r e tu r n m igration, c irc u la r m igration, an d p e r ­ manent settlem en t, - an d th e o p e ra tio n , a d v a n ta g e s an d d is­ ad v an tag es of each s tr a te g y a re exam ined. F inally, c o n sid e r­ ation is given to governm ent atte m p ts to red u c e th e r u r a lu rb a n flows. It is o b se rv e d th a t in p ra c tic e in te rn a l m igration con tro ls a re d ifficu lt to en fo rce an d a re of limited effe c tiv en e ss. It is a rg u e d th a t policies which seek to deny th e b e n e fits of u rb a n life to d isa d v a n ta g e d ru ra l dw ellers a re socially re g re s s iv e , an d th a t w hat is re q u ire d is a po sitiv e policy aimed a t th e developm ent of r u r a l a re a s . T h is would re q u ire a sig n ifican t re -o rie n ta tio n of re s o u rc e s ( e .g . v ia th e ta x sy stem , a g ric u ltu ra l p ric in g o r d ire c t in v e stm en t) a n d ru n co u n ter to th e in te r e s ts of u rb a n -b a s e d pow er g ro u p s . T h is s u g g e s ts th a t such a s tra te g y is u nlikely to b e widely adop ted an d th a t r u r a l- u r b a n m igration will continue to b e a fe a tu re of th e population g eo g rap h y of th e T h ird World for th e forseeable fu tu re . F or most of th is c e n tu ry th e dom inant d irectio n o f p o p u ­ lation movement in w estern c a p ita list so cieties was from ru r a l to u rb a n a re a s . Since th e e a rly 1970s, ho w ever, a r e v e rs a l of 8

IN T R O D U C T IO N

th is tre n d h as become a p p a re n t an d th e phenom enon of c o u n te ru rb a n isa tio n h as become a major com ponent of contem ­ p o ra ry population dynam ics. In C h a p te r 8 T ony Fielding exam ines th is p ro c e ss in a r e p re s e n ta tiv e a r r a y of c o u n trie s and th e n co n sid e rs th e v a rio u s e x p la n a tio n s fo r th e em ergence of such a p a tte r n . A tten tio n is given f ir s t to th e evid en ce for the "population tu rn a ro u n d " in USA w here dom inant elem ents in th e post-1970 population re d is trib u tio n in c lu d e d , (a ) a negative re la tio n sh ip betw een population grow th a n d u rb a n size, (b ) a p o sitiv e re la tio n sh ip betw een p o pulation grow th and d istan ce from th e city c e n tr e , an d (c ) a n e t m igration gain by non-m etropolitan a re a s a t th e e x p e n se of m etropolitan a re a s. T he e x iste n c e of sim ilar tr e n d s in o th e r c o u n trie s is revealed b y detailed co n sid eratio n of A u stra lia , Jap an and F rance. In A u stra lia , while th e tu rn a ro u n d was more th a n a simple re v e rs a l of th e p re v io u s p a tte rn of u rb a n isa tio n (w ith , for exam ple, population lo ss ex p e rie n c ed by rem oter ru ra l regions as well a s la rg e u rb a n c e n t r e s ) , common fe a tu re s included a n et in te rn a l m igration loss from th e major cities and th e em ergence of a "su n b elt" phenom enon in Q ueensland. Similarly in h ig h ly -u rb a n is e d J a p a n , an d in F ra n c e , a r e v e r ­ sal of m igration flows in fav o u r of r u r a l a re a s became ap p aren t aro u n d 1970. A ttention th e n tu r n s to c ritic a l analysis of th re e major s e ts of a rg u m e n ts to ex plain c o u n te r­ u rb a n isa tio n . The f ir s t su g g e stio n th a t it is a s ta tistic a l arte fa c t a ris in g from th e u n d e rb o u n d in g o f de facto u rb a n are a s is re je c te d since it is cle a r th a t th e p ro c e ss in volves more th a n sub u rb a n isa tio n . A second paradigm s u g g e s ts th a t place p re fe re n c e s can b e st explain th e c h a n g in g p a tte r n s of net m igration. It is co n clu d ed , h o w ev er, th a t since m igration decisions a re normally c o n stra in e d by in com e-related fa c to rs th is argum ent h as at b e s t a s u p p o rtin g role an d h a s g re a te st relevance fo r re tire m e n t m igration and to u ris t em ploym ent. The th ir d model s u g g e s ts th a t c o u n te ru rb a n isa tio n r e s u lts from world economic conditions (in p a rtic u la r th e recessio n and e n e rg y c ris is ) w hich im proved th e position of ru ra l regions re la tiv e to m etropolitan a re a s . T h is a rg u m e n t, b ased on p arallels with th e 1930s, is u nderm ined by sig n ifican t tem poral d iffe re n c es (su c h a s , th e c u r r e n t av ailability o f social w elfare program m es) and ev idence which s u g g e s ts th at the population tu rn a ro u n d commenced p rio r to th e economic c rise s of 1973. T he a n a ly sis co ncludes by id e n tify in g th e ex p lan ato ry pow er of an ap p ro ach b ased on th e g e o g rap h y o f p ro d u ctio n . U tilising th e concept of th e sp a tia l division of labour th is s u g g e s ts th a t c o u n te ru rb a n isa tio n may be d u e to a sh ift from regional se c to ra l specialisatio n (in which each place co n cen trated on all ta s k s involved in p ro d u c in g a good) to a new spatial division of la b o u r in which p laces a re d iffe re n ­ tiated with re sp e c t to th e p a r t th e y p lay in th e p ro d u c tio n p ro c e ss. T h is su g g e s te d th a t th e dominance of RSS up to 1960 p ro d u ced u rb a n isa tio n w h ereas sin ce th e 1970s th e NSDL 9

IN T R O D U C T IO N

h a s allowed some form s of employment ( e .g . ro u tin e p ro ­ duction) and em ployees ( e .g . m anagers) to d e c e n tra lise. F u rth e r em pirical ev id en ce is re q u ire d to su p p o rt the RSS-NSDL tra n sitio n model b u t p relim in ary in d ica tio n s a re th a t it o ffe rs a p o ten tially u se fu l an aly tical fram ew ork. In C h a p te r 9 M artin C adw allader exam ines rec en t re se a rc h in to in te r-re g io n a l m igration an d in tr a - u r b a n re s i­ dential m obility. The sp a tia l p a tte r n of regional m igration flows an d th e re la tiv e im portance of p u sh and pull fa c to rs have been th e su b je c t of in v e stig a tio n e v e r since R avenstein form ulated h is "laws" of m igration. While th e im portance of d istan ce and d irectio n h as been d em o n strated it may be q u e s ­ tioned w h eth er th e ir in d iv id u al e ffe c ts can be isolated from those of o th e r fa c to rs . A ttem pts to id e n tify th e re lativ e im portance of d iffe re n t d e te rm in a n ts of m igration u sin g th e g ra v ity model an d single eq u atio n models have in d ica te d th e relevance of unem ploym ent r a te s , income lev els, age and education d iffe re n c e s, and p re v io u s m igration p a tte r n s as well as environm ental fa c to rs. S ev eral sta tis tic a l ( e .g . m ulticollinearity) and th e o re tic a l problem s ( e .g . th e two-way relatio n sh ip betw een m igration and th e e x p la n ato ry v a riab les) a re id en tified an d possib le so lu tio n s s u g g e s te d . T hese include field th e o ry , cannonical co rrelatio n a n a ly s is, and th e u se of s tru c tu ra l eq u atio n models which specify both th e linkages betw een d ep e n d e n t an d in d e p e n d e n t v a ria b le s and also th e in te rre la tio n sh ip s among th e initial cau sal v a ria b le s. The con trib u tio n of dynam ic models to th e s tu d y of tem poral change in m igration p a tte r n s ( e .g . via Markov chain an aly sis o r tim e-series te c h n iq u e s such as m oving a v era g e an d a u to ­ re g re ssiv e models) is also d is c u ss e d . A ttention th e n tu r n s to th e b ehavioural ap p ro ach to m igration, c e n trin g on th e investm ent in human cap ital th e o ry an d on th e co n cep ts of place u tility and re sid e n tia l p re fe re n c e . In ad dition to the links betw een p re fe re n c e s and m igration b e h av io u r th e n a tu re of p re fe re n c e s h as b een ex p lo red an d th e u tility of sev e ra l p ro c e d u re s (su c h as conjoint m easurem ent te c h n iq u e s and m ulti-dim ensional scalin g ) is illu s tr a te d . It is su g g e ste d th a t fu r th e r p ro g re s s in u n d e rs ta n d in g in te r-re g io n a l m igration may be gained by com bining macro and m icro-scale a p p ro ach es. S everal im p o rtan t re s e a rc h q u e stio n s a re id e n t­ ified in clu d in g (a) th e s tu d y of tem poral c h a n g e s in m igration p a tte r n s , (b ) in co rp o ratio n of in d iv id u al and in stitu tio n a l c o n stra in ts in to m igration m odels, an d (c) g re a te r atte n tio n to th e co n seq u en ces as well a s th e c a u se s of m igration. The discu ssio n th e n tu r n s to co n sid e r re sid e n tia l movement within cities. Spatial v a ria tio n s in mobility ra te s a re id e n tifie d and possible e x p la n a to ry fa c to rs , (re la te d to dem ographic, social, economic an d h o u sin g c h a ra c te ris tic s of th e u rb a n e n v iro n ­ ment) a re exam ined. As at th e reg io n al le v e l, a g g re g a te analy sis of th e role of d istan ce and d ire c tio n in in tr a - u r b a n movement is complemented by co n sid eratio n of b eh avioural 10

IN T R O D U C T IO N

models which focus on th e in d iv id u al m ig ran t. It is o b se rv e d th a t alth o u g h th e y a re in te r r e la te d , th e major com ponents of the m igration p ro c e ss can be exam ined sin g ly in an a ttem p t to illum inate th e u n d e rly in g m echanism s. T h e decision to move, for exam ple, h as been in v e stig a te d u sin g co n c ep ts su c h as resid en tial s tr e s s . S tu d y of th e se a rc h p ro c e ss h as co n sid ered inform ation s o u rc e s , optimum sto p p in g ru le s and th e location of se a rc h a c tiv ity ; while atte m p ts have b een made to model resid en tial choice p ro c e s s e s by m eans o f log lin e a r m odels. In most form ulations to d a te , ho w ev er, in su ffic ie n t a tte n tio n has been given to th e c o n s tra in ts on in d iv id u al m igration. It is su g g e ste d th a t f u r th e r in v e stig a tio n of th e e ffect of h o using supply c o n s tra in ts on m igration b e h a v io u r could in c re a se th e p re d ic tiv e ability of e x is tin g models an d en hance th e ir u tility in term s of public policy form ulation. T he explanation an d p re d ic tio n of human b e h a v io u r in space is th e g en eral o bjective to which q u a n tita tiv e population g e o g ra p h e rs seek to make a c o n trib u tio n . Two specific a re a s in which population m odellers have shown in te re s t a re th e behaviour of p o p u latio n s in th e p a st an d how population may develop in th e th e f u tu r e . In C h a p te r 10 Philip R ees, concen­ tra tin g on p re d ic tiv e form ulations, e x p lain s th e p rin c ip al conceptual an d methodological issu e s u n d e rly in g population modelling. Four fundam ental co n cep ts a re exam ined. F ir s t, th e concept of th e ideal d a ta se t an d life h isto ry fram ew orks, second, th e s ta te s of th e sy stem , t h ir d , th e ty p e of tr a n s f e r data and model ty p e , and fo u rth th e ag e-tim e plan u sed in o b se rv in g or m easuring dem ographic v a ria b le s. T he p ro p e rtie s of an ideal d a ta se t em bodying th e life h isto rie s of th e p o p u ­ lation a re d e ta ile d , an d th e p o ten tial u tility of th e OPCS longitudinal stu d y n o ted . T he ch ief im portance o f su ch a conceptual fram ew ork is th a t it en ab les re s e a r c h e rs to ev alu ­ ate th e ir d a ta a g a in st an ideal an d so reco g n ise any deficiencies o r b ia s s e s. T he second key co ncept r e f e r s to th e ways in which a population is classified a n d to th e movement of in d iv id u als betw een su ch c la sse s o v e r th e ir lifetim e. Several exam ples of th e k in d of s ta te to s ta te tr a n s f e r s th a t have commonly been b u ilt in to population models a re p ro v id ed ( e .g . betw een age g ro u p s , m arital co n d itio n , la b o u r force s ta tu s , and geographic a re a s ) a n d th e problem s of o p e r­ ationalising th e se a re co n sid e re d . T he d iffic u lty of in c o r­ p o ra tin g sev eral dim ensions in to a model is exam ined. T h ird ly , th e way in w hich d iffe re n t k in d s o f tr a n s f e r data affect th e calculation of multi s ta te tra n s itio n p ro b a b ilitie s and influence th e in te rp re ta tio n of model o u tp u ts is d isc u sse d . The basic d istin ctio n is draw n betw een tr a n s f e r s a s tr a n ­ sitio n s, m oves, and last m igratio n s. It is em phasised th a t in developing a multi s ta te model of a pop ulation it is f ir s t n e c e ssa ry to a sc e rta in th e ty p e of tr a n s f e r d a ta available and th e n adopt th e a p p ro p ria te model s tr u c tu r e . T he u se o f th e method of dem ographic acco u n ts in e stim atin g m ulti sta te 11

INTRODUCTION

mobility is th en illu s tra te d . The final set of concepts con­ sidered concerns th e age-tim e plan (ATP) employed in observing o r m easuring dem ographic v ariab les. The n a tu re of four ATPs is explained with th e aid of Lexis diagram s, and the ben efits and problem s of employing each are identified. Attention th en tu rn s to two fundam ental models in population geography - th e cohort su rv iv al and th e life table models and how th ese can be linked to th e concepts outlined. A general formulation for m ulti-state projection models is th e n p rese n te d and critically a sse sse d . Some problem s in imple­ menting th e projective models devised are identified and possible solutions su g g e ste d . To be su ccessful population modelling must be based on sound inform ation on th e n atu re of the system being modelled, on th e ty p e of population sta te s necessary for the problem , and on th e ty p e of tra n s fe r data available for th e system u n d e r in v estig atio n .

12

C h ap ter One THEORY AND METHODOLOGY IN POPULATION GEOGRAPHY R. I. Woods

Population g eo g rap h y h as no one th e o r y , methodology o r , fo r th a t m a tte r, d efin itio n . It is a widely reco g n ised su b -fie ld of geo g rap h y as a te a c h in g su b je c t a n d w ork on population m atters is prom inent in th e re s e a rc h d iscip lin e th a t is geo­ g ra p h y . B ut th e d istin c tio n s betw een g eo g rap h ies of p o p u ­ latio n , w here population is m erely one a sp e c t of a complete human g e o g ra p h y ; sp atial p e rs p e c tiv e s in population stu d ie s or d em ography, and population g eo g rap h y as a se p a ra te en tity in its own rig h t a re excep tio n ally b lu r r e d . Some of th ese d ifficu lties re la te to th e in h e re n t problem s faced in defining g eo g ra p h y , b u t o th e rs stem from th e n a tu re of p o p u ­ lation stu d ie s as a d iffu se m u lti-d iscip lin ary specialism . In o rd e r to clarify w hat a re th e im portant elem ents in th is chaotic sta te of a ffa irs we m ust b eg in by exam ining th e orig in s of com peting d efin itio n s of popu latio n g e o g ra p h y . T his will pro v id e an in tro d u c tio n to what will be th e main concern of th is c h a p te r: a d iscu ssio n of th e th e o re tic a l and m ethod­ ological developm ents in b o th th e g e o g ra p h e r's ap p ro ac h to population a n d , since it may be th a t population g eo g rap h y is also b ein g done b y n o n -g e o g ra p h e rs , population stu d ie s in g en eral. DEFINITIONS Glenn T T re w a rth a 's p re s id e n tia l a d d re s s to th e A ssociation of American G eo g rap h ers in 1953 p ro v id e s a co n v en ien t s ta r tin g point fo r o u r co n sid eratio n of th e v a rio u s d efin itio n s o f p o p u ­ lation g e o g ra p h y . T re w a rth a (1953, see also K o sin sk i, 1984) was co n cern ed w ith th e need fo r g e o g ra p h e rs to tr e a t p o p u ­ lation m atters as a p rin c ip a l su b -d isc ip lin e (w ith c u ltu ra l and p hy sical g e o g ra p h y ) of a te a c h in g and re se a rc h su b je c t th a t was essen tially h olistic in form . B u t a p a rt from bem oaning th e neglect of population he p ro p o sed 'a system fo r population geo g rap h y ' which ev en th ir ty y e a rs o n , is still well w orth co n sid e rin g . 'T h e g e o g ra p h e r's goal in an y o r all a n a ly ses of

THEORY AND METHODOLOGY IN POPULATION GEOGRAPHY

population is an u n d e rsta n d in g of th e regional d ifferences in the e a rth 's covering of people. J u s t as area of differentiation is the theme of geography in g e n e ra l, so it is of population geography in p a rtic u la r' (T re w a rth a, 1953, 87). Population geography is th e 'a re a analysis of population', and so T rew arth a's 'system ' lists 'th e kinds of population fea tu res to be observed and compared in d iffe re n t a re a s '. A diagram atic summary of T rew arth a's (1953, 88-87) 'system ' is illu stra te d in Figure 1 .1 . The objective, shown in th e to p -c e n tre box, is to u n d e rsta n d th e area differen tiatio n of population, b u t th is is accomplished via at least th re e ro u te s: h isto rical, numerical and qualitative. The second box in Figure 1.1 seems th e most im portant since it covers m ortality and fertility variations (2b): the d istrib u tio n of population, settlem ent size and urbanisation (2 d ): m igration at v ario u s scales (2e): b u t is also linked with notions of reso u rces and c a rry in g capacities (2c). The th ird box relates to area differentiation in the qualities of population; some of which are physical (3a) and some socio-economic (3 b ). The point needs to be em phasised th a t T rew arth a's 'system ' would re g a rd area differentiation in , for example, levels of economic development as p a rt of popu­ lation g eography. This is en tirely co n sisten t since th e o th e r two th ird s of the geography trian g le are physical and cu ltu ral, n eith er of which would presum ably deal with economic development as a central issu e . Although T rew artha arg u ed th e case for population as the 'pivotal element in g eography' he was also aware th a t, 'th e re is bound to be lack of agreem ent on th e full content of the field of population geography and adm ittedly th e re is no one way o r b est way of o rd e rin g and a rra n g in g the topics to be included. Still, in most disciplines and b ran ch es of d isci­ plines, th e re is a core of content on which th e re is reaso n ­ able agreem ent, even though th e full content and its a rra n g e ­ ment may b ear th e stamp of individual a u th o rsh ip ' (T rew arth a, 1953, 87). D espite changes in geography as a teaching subject and re se a rc h discipline many a u th o rs have used T rew arth a's 'system ' o v er th e last th ir ty y e a rs. John I. C larke's (C lark e, 1965 and 1972), approach has been p a rtic u ­ larly influential. 'Population g e o g ra p h y ... is concerned with dem onstrating how spatial variatio n s in th e d istrib u tio n , composition, m igrations and grow th of populations a re related to spatial variatio n s in th e n a tu re of p la c e s', and th u s 'population g eo g rap h ers endeav o u r to u n rav el th e complex in te r-re la tio n sh ip s betw een physical and human environm ents on the one h an d , and population on th e o th e r. The expla­ nation and analysis of th e se in te r-re la tio n sh ip s is th e real substance of population geo g rap h y ' (C larke 1972, 2; see also C larke, 1984). More re c e n tly , Robin J . P ry o r (1984) begins his review of methodological problem s in population geography with: 'I t is assumed h ere th a t population geography deals with th e analysis and explanation of in te rre la tio n sh ip s betw een 14

THEORY AND METHODOLOGY IN POPULATION

A diagram atic summary of G .T . T re w a rth a 's 'system for population g e o g ra p h y '. (S o u rce: b ased on T re w a rth a , 1953, 88-89)

GEOGRAPHY

M Fig. 1.1 01

THEORY AND METHODOLOGY IN POPULATIO N GEOGRAPHY

population phenomena and th e geographic c h a ra c te r of places as both v a ry th ro u g h time and space. Population phenomena include the dynamics of population d istrib u tio n , u rb a n /ru r a l location, den sity and grow th (o r d ecline); m ortality, fe rtility , and m igration; and s tru c tu ra l c h a ra c te ristic s including age, sex , eth n icity , marital s ta tu s , economic com position, national­ ity , and religion' (P ry o r, 1984, 25). Here we have a workable and unified definition th a t links T re w a rth a 's 'system ' with C larke's concern with spatial variations in populations and places. This broad definition is also reflected in Daniel Noin's Geographie de la Population (1979) and J a rg e n B ohr's iBevOlkerungsgeographie (1983). Both a u th o rs are concerned with the spatial d istrib u tio n of p o p u latio n , with the components of its grow th and with th e ch a ra c teristic s of populations. Noin's (1984) su rv e y of the contents of popu­ lation geography textbooks p ublished d u rin g the last tw enty years shows q uite clearly th a t the broad definition has been the one most widely adopted and th a t its chief d istin g u ish in g characteristic is a close ad herence to T re w a rth a's 'system ' b u t especially boxes 2d, 3a and 3b. O th er definitions and approaches have been pro p o sed , how ever. The narrow definition is to be found in Hoods (1979, 1982) and Jones (1981). T h eir ap p ro ach , both sta te d and implied, is largely concerned with m aterial related to boxes 2b and 2e in Figure 1.1. T hat is v ariatio n s in population dynam­ ics approached via an analysis of th e m ortality, fe rtility and migration components at v arious scales, in the case of Jones (1981), and more generally the stu d y of population from the spatial p ersp ectiv e. The narrow definition deliberately neglects population d istrib u tio n and re d istrib u tio n (2d) and the 'q u alities of populations' (3 ), except in the sense th a t the la tte r affects the com ponents. T his attem pt to narrow the field of view and to develop a dem ographic geography o r spatial dem ography has not gone unchallenged by th e advo­ cates of th e broad definition (se e , fo r example, C larke, 1980, 1984) who, as we have se e n , still ad h ere to T rew arth a's 'system ' of Figure 1 .1 . They would answ er C larke's (1980, 368) qu estio n , 'How much more dem ographic should population geography become?' in a way th a t would accept th e techniques of analysis developed by d em ographers, b u t would reject the wider methodology and objectives. Newman and Matzke (1984) seem to su g g est a sensible compromise. For them 'population geography is a relatively open field of in q u iry . It does have a recognisable co re, b u t th e re is considerable room fo r many issu es th a t relate to people and th e ir w ell-being' (Newman and Matzke, 1984, 6 ). However, the core com prises th e demo­ graphic v ariab les, population change and d istrib u tio n ; while beyond may lie 'social and economic in d icato rs' ( e .g . language, e th n ic ity , religion, occupation); resid en tial 16

THEORY AND METHODOLOGY IN POPULATIO N GEOGRAPHY

c h aracteristics' (ru ra l and u rb a n ); a n d 'population in its bro ad er human context' ( e .g . re so u rc e s, politics, p o licy). It might be objected th a t an ex ten d ed debate o v e r th e definition and content of population geography is bound to be arid at b e s t, d e stru c tiv e at w o rst, th a t population geography should be what g eo g rap h ers active in teach ing and re se a rc h on population do. T here is no need fo r e ith e r a b road o r narrow definition where in te r-d isc ip lin a ry boundaries a re being crossed with in creasin g ease and b y grow ing num bers. All th is may be so, b u t one is left to p o n d er a rid d le set by Clarke (1977, 136), 'Why has th e academic influence o f popu­ lation geo g rap h ers been less significant th an th e ir num bers would su g g est?' 'Academic influence' will be taken to stem from th e theoretical in sig h ts provided by a discipline o r su b ­ discipline to g eth er with th e empirical know ledge, b u t p e rh a p s especially th e useful know ledge, accum ulated and th e ability to pred ict su ccessfu lly . Using th ese c rite ria it may be appreciated why geography as a re se a rc h discipline lacks academic influence; why within the discipline the influence of population geography and population g eo g rap h ers has been relatively insignificant; and why th e same could be said of geography's influence on dem ography o r population stu d ie s. As Jones (1981, vi) has rem arked, 'Population g eo graphers have not fig u red among th e storm troopers o f methodological transform ation in geography in recent y e a r s . . . ' My answ er to C lark e's riddle is to arg u e th at because of the broad definition population g eo g rap h ers have sp read them selves too thinly o v er too larg e a field; th a t generally they have not m astered th e tech n iq u es of dem ography as Trew artha (1953) advised them to; and th a t they have been unadventurous in th e ir willingness to develop new concepts for u n d erstan d in g and p red ictio n . Of co u rse th e re have been exceptions and th e re are signs of ch an g e, b u t most are v ery recen t. I shall consid er th e th eo ry and method asp e cts o f th is argum ent in the nex t section, and only two examples of th e exceptions must suffice at th is sta g e . Regional population forecasting, once describ ed as having rem ained p e rip h e ra l to population geography (C lark e, 1980, 389), h as shown its e lf to have g reat v itality and p ractical value (see Hoods and R ees, 1986). Similarly th e ability of population g eo g rap h ers to assemble and manipulate larg e d ata s e ts of u seful knowledge in ways th a t are convenient to o th e r re s e a rc h e rs , p la n n ers and decision makers can only enhance th e ir influence (se e , for example, R hind, 1983). I shall re tu rn to th is question of academic influence la te r, b u t at th is stag e it is n ecessary to rep eat th a t th e re is no one ag reed definition of population geo graphy; th a t the so-called broad and narrow approaches a re not mutually ex clu siv e, ra th e r th ey re p re se n t d ifferen ces of em phasis, and th a t th e p ersiste n c e of u n c e rta in ty may p rove a source o f 17

T HEORY AND METHODOLOGY IN P O P U L A T IO N G EOGRAPHY

w eak n ess. We m ust now tu r n to co n sid e r th e main them e of th is c h a p te r, th e o re tic a l an d methodological developm ents, b u t th e issu e of definitional d iv e rs ity will rem ain in th e b a c k ­ gro u n d . THE NEED FOR THEORY All th e a d v a n ta g e s of w orking w ith a th e o re tic a l fram ew ork need not be sp e lt out h e r e , b u t it may be w orth em phasising fou r p a rtic u la r p o in ts which a re h elp fu l in population geo­ g ra p h y . F ir s t, th e u se of th e o re tic a l s ta te m e n ts, th a t is statem en ts of p ro sp e c tiv e a sso ciatio n , help to focus re se a rc h which might o th erw ise become d iffu s e , aim less o r o v e rem pirical. Second, th e u se of a b ro a d th e o re tic a l fram ework perm its in te r-d is c ip lin a ry com parison to be made more fo rcib ly . T h ird , th e consciously in te rro g a tiv e sty le of th e o ry co n stru c tio n an d d e s tru c tio n aid s th e definition of p rio ritie s and c re a te s a sen se of p ro g re s s when a su ccession of p a rtia l solutions a re forthcom ing. F o u rth , th e adoption of a th e o r­ etical fram ew ork m akes ex p licit th e need to tackle issu e s of p u rp o se , m eaning, u n d e rs ta n d in g , ex p lan atio n and in te r p r e t­ ation which might o th erw ise rem ain a t a su b co nscious level. An e ffect of re c o g n isin g th e s e p o in ts will be to p u sh population g e o g ra p h e rs c lo se r to th e m ainstream of m ethod­ ological d eb ate th a t h as in fu se d human g eo g rap h y in th e 1980s. F ig u re 1.2 in d ic a te s some of th e is s u e s th a t will need to be ta c k le d . T he u p p e r le ft pane of th e window shows exam ples of th e levels of th e o ry av ailable in g en eral and em phasises both th e need to a g re e upon th e p u rp o se of th e o ry c o n stru c tio n an d th e c rite ria to be u sed in th eo ry validation (how th e o rie s a re to be ju d g e d ). T he low er left pane lis ts five d istin c tiv e m ethodologies which a re c u rre n tly in u se am ongst g e o g ra p h e rs , b u t it does so in a way th a t s u g g e s ts a se q u en tial o rd e r from em piricism to stru c tu ra lism which is at le a st p a rtia lly in ste p with re c e n t developm ents in human g eo g rap h y (J o h n s to n , 1983). T he two p a n e s on th e rig h t have been le ft to be com pleted by th e r e a d e r , b u t th e re s t of th is and s u b se q u e n t c h a p te rs will p ro v id e d iscu ssio n of a to e and exam ples of 1 to 5. Purpose C onsideration of p u rp o se not only r e tu r n s u s to definitional issu e s in tro d u c e d ab o v e, b u t it also makes u s aw are of th e d iffe re n c es in levels of u n d e rs ta n d in g th a t a re b e in g so u g h t. For exam ple, th e re is a c le a r d istin c tio n betw een s tu d ie s th a t seek to model o r fo re c a st m igration flows u sin g a black box tech n iq u e an d th o se th a t attem pt an in te rp re ta tio n o f human b eh av io u r an d decision m aking w ith r e s p e c t to m obility. T he form er u sed th e o ry in a m odelling se n se ; th e y a re concerned 18

T HEO RY AND METHODOLOGY IN P O P U L A T IO N GEOGRAPHY

General

S pecific to population geography

purpose validation

Theory

levels ; micro middle range grand

empiricism positivism

M ethodology

behaviouralism humanism structuralism

Fig. 1.2

A th e o re tic a l window.

with th e re la tio n sh ip s betw een o u tp u t an d in p u t, with resp o n se s to p aram eter c h a n g e s an d w ith th e need to p re d ic t fu tu re p a tte r n s an d d is trib u tio n s . T he la tte r have more intan g ib le o b je c tiv e s. T hey deal w ith notions like place u tility , sa tisfa c tio n , environm ental s t r e s s , sta g e in th e life cycle, b o u n d ed an d selectiv e ra tio n a lity and c o n stra in e d action. T hese s tu d ie s seek a b ro a d e r u n d e rs ta n d in g of why ind iv id u als o r g ro u p s m igrate and w here th e y move to , b u t th e re a re no ag re e d c rite ria on what u n d e rs ta n d in g should mean. While some r e s e a rc h e rs deal w ith th e c o rre la te s o f flow p a tte r n s (G reenw ood, 1981) o th e rs a re co n ce rn ed w ith the c h a ra c te ristic s of m overs com pared w ith s ta y e rs (S p e a re , 1971, White an d H oods, 1980) o r th e psychology o f decision making and im plem entation (W olpert, 1964, 1965, 1966; L ieb er, 1978; D e s b a ra ts , 1983). All c o n trib u te to th e common sto c k of inform ation on m igration, all u se th e o ry to some e x te n t, b u t even th o u g h th e ultim ate o bjective can be s ta te d , m ethods a re as d iv e rse as th e in d iv id u al r e s e a rc h e rs u s in g them . As fa r a s th e u se of th e o ry b y g e o g ra p h e rs stu d y in g m igration is co n cern ed while th e g e n e ra l p u rp o se is cle a r th e re is little evidence th a t th e d iv e rs ity of s h o rt-te rm objec­ tiv es and m ethods has been ex p licitly rec o g n ised o r th a t th e variable s ta tu s of conclusions h a s b een a ss e sse d in w ays th a t reflect such d iv e rs ity . Validation How a re th e o rie s to be a sse sse d ? Can th e y be p ro v e d o r merely tem porarily accep ted while ev id en ce fo r conclusive rejection is lacking? T h ese a re im p o rtan t q u e stio n s which 19

THEORY AND METHODOLOGY IN P O P U L A T IO N G EOGRAPHY

re q u ire c arefu l co n sid eratio n w hen th e o re tic a l fram ew orks are used in p o pulation g e o g ra p h y , y e t th e y a re o ften e ith e r ig n o red o r th e a lte rn a tiv e forms of a n sw e rs a re not recog­ nised . T he b ro ad d efinition of popu latio n g eo g ra p h y in clu d es settlem ent g eo g rap h y (2a in F ig u re 1 .1 ) and th u s c e n tra l place th e o ry . T he h is to ry of th e developm ent and u se of C h ris ta lle r's th e o ry p ro v id e s an in te r e s tin g case s tu d y o f th e rise an d fall of a v e ry p a rtic u la r form of th eo re tic a l fram e­ w ork. C lassical c e n tra l p lace th e o ry is a n o rm a tiv e-d ed u ctiv e th e o ry b a se d on a num b er of sp ecific environm ental and behavioural assu m p tio n s. Once th e s ta g e h a s been s e t an d the ca st selected th e p lay u n fo ld s in a h ig h ly o rd e re d fash io n , th e final outcome is c le a r an d th e p r o g r e s s to it in ex o rab le . In te re s t in C h rista lle r a n d L osch 's v e rsio n s of th e th e o ry was rek in d led in th e 1950s and 1960s am ongst g e o g ra p h e rs who sou g h t to move bey o n d th e d e s c rip tio n and classification of settlem ent ty p e s who re q u ire d fo r th e ir p u rp o se a rig o ro u sly developed th e o ry of th e location an d fu n ction of se ttle m e n ts. The f ir s t inclin atio n of th e s e g e o g ra p h e rs was to 't e s t ' the th e o ry . T hat is to d e riv e from c e n tra l p lace th e o ry h y p o th ­ eses which could in tu r n y ield em pirically verifiab le p re ­ dictio n s. S u rp risin g ly many of th e e a rly te s ts rev ealed th a t th e re was r a th e r more re g u la rity in settlem ent p a tte r n s th a n one might have ex p e c te d a p rio ri an d th a t c e rta in a sp e c ts of u rb a n functional h ie ra c h ie s could be id e n tifie d ( B e rr y , 1967; B e rry an d H orton, 1970). Where th e re was a poor c o rre sp o n ­ dence betw een o b se rv e d and e x p e c te d , g e o g ra p h e rs w ere likely to relax th e assu m p tio n s on w hich th e th e o ry was b ase d . Since even in Iowa an d E ast Anglia th e iso tro p ic p lain s were b o u n d ed an d u n d u la tin g how could one e x p ect p e rfe c t hexagons to em erge? T he ra tio n a lity of man as homo economicus also came in to q u e stio n . Was m otorised man in d if­ fe re n t to th e cost e ffe c ts of re la tiv e ly s h o rt in c re a se s in jo u rn e y to p u rc h a s e an d th u s capable of ig n o rin g th e n e a re st reta il o u tlet fo r a d e s ire d good? Even if one a c c e p ts an affirm ative an sw er it m ust be rec o g n ise d th a t th e economic o rd e rin g of sp ace is not e n tire ly chaotic a n d th u s th a t s e ttle ­ ment p a tte r n s may p ro v e to be no n -ran d o m . All of th is p re s u p p o s e s th a t classical c e n tra l place th e o ry is e x p re s s e d in a form th a t is capable of em pirical v e rifi­ cation. B ut th is may p ro v e a d u b io u s p o sition to ta k e . In its p u r e s t form c e n tra l place th e o ry is b eyond v e rific a tio n , r a th e r it p ro v id e s a th e o re tic a l fram ew ork of th e id eal ty p e form . It is c o n s tru c te d in su ch a way th a t th e com parison of o b serv ed and e x p e c te d will mainly s e rv e to h ig h lig h t ir r e g u ­ la ritie s in th e o b se rv e d p a tte r n since th e assum ptions on which th e th e o ry is b a se d a re h ig h ly id e alise d . T he th e o ry its e lf may only be a ss e s s e d in term s of it s in te rn a l logic, th a t is th e m anner in which conclusions can be co n siste n tly d eriv ed from in itial a ssu m p tio n s. Once th e th e o ry h a s p assed 20

T HEO RY AND METHODOLOGY IN P O P U L A T IO N GEOGRAPHY

this t e s t, its main function is to rev eal th o se non-econom ic a sp e c ts, su ch as environm ental v a ria tio n an d u n eq u al re so u rc e allocation, th a t d is to rt th e p u re ly economically d eterm ined form of settlem ent p a tte r n g e n e ra te d by c e n tra l place th eo ry (see W ebber, 1972, 88-116; L eib en stein , 1976). T his example s e rv e s to raise some in te re s tin g g en eral poin ts re g a rd in g th e form of validation to be u se d in p o p u ­ lation g e o g ra p h y . It s u g g e s ts th e need fo r flex ib ility a n d th e value of avoiding s ta rk ly d efin ed c a te g o rie s - tr u e -fa ls e , a c c e p ted -re je c te d - an d above all i t r e f e r s u s b ack to th e q uestion of p u rp o s e , w hat is o u r o b jectiv e in c o n stru c tin g a th eo retical framework? Levels: M icro-theory The m atter of p u rp o se also lead u s on to c o n sid er th e levels at which th e o rie s can be c o n s tru c te d . M erton (1967, 39) has d istin g u ish e d th re e d istin c t c a te g o rie s which he labels micro­ th e o ry , middle ra n g e th e o ry an d g ra n d th e o ry . Each of th e se levels re la te s to a p a rtic u la r way of c o n s tru c tin g know ledge. For exam ple, an d to ov ersim p lify , m icro -th eory deals w ith th e b eh av io u r of th e e sse n tia l b u ild in g blo ck s o f a society o r economy in th e ir in d iv id u al form s. H ere one se ek s to u n d e r­ sta n d th e actions of in d iv id u al p e rs o n s , o r families o r h o u se­ holds, how th e y th in k , p erc e iv e th e ir re la tiv e p o sitio n s, act to change an d re a c t to th e ir circ u m sta n c es. Middle ra n g e th eo ries a re concern ed w ith th e c h a ra c te ris tic s of a g g re g a te s , g ro u p s of people d efin ed in s p a tia l, o ccu p atio n al, e th n ic e tc cate g o rie s. T his form of th e o ry d eals ex p licitly with d e p e n ­ den t and in d e p en d e n t v a ria b le s , w ith th e m u ltiv ariate a sso c i­ ation betw een a num ber of th e la tte r an d one of th e form er. G rand th e o ry is r a th e r more d ifficu lt to d efine p re c is e ly , b u t its sp h e re is ty p ified by lo n g -term so cial, economic and dem ographic ch a n g e . For population g e o g ra p h e rs dem ographic tra n sitio n th e o ry p ro v id e s p e rh a p s th e most obvious exam ples (see S k in n e r, 1985, fo r a g e n e ra l d isc u s s io n ). In te re s t in m icro-scale th e o ry am ongst population geo­ g ra p h e rs has re la te d mainly to th e ir co n c e rn w ith m igration stu d ie s , th e ir d e sire not only to d e sc rib e th e c h a ra c te ris tic s of m ig ra n ts, o rig in s , d e stin a tio n s an d flow s, b u t also to u n d e rs ta n d how an d why in d iv id u a ls decide to move (W hite, 1981). B ut th e se id e a s may also b e a p p ro p ria te w hen dealing with o th e r dem ographic e v e n ts (w hen an d whom to m a rry , how many ch ild re n to have and w hen, w h e th er to get d iv o rc e d ). Let u s co n sid e r th e case of m arriag e , a r a th e r n eg lected a rea of population g eo g ra p h y . C ro ss-c u ltu ra l d efin itio n s of m arriage e n c o u n te r c e rta in problem s for th e significance and m eaning of m arriage v a rie s in im portant re s p e c ts betw een so cieties. T he most im portant asp ect re la te s to th e legal r ig h ts of c h ild re n b o rn to p a re n ts who a re m arried . M arriage th u s becom es an in s titu tio n which 21

THEORY AND METHODOLOGY IN P O P U L A T IO N GEO GR A PHY

legitim ises re p ro d u c tio n , inv o lv es a more o r le ss perm anent sexual union (im plying th a t b o th p a r tn e r s m ust b e sexually m ature) and th e o n set of w hich is sig n ified by a pu b lic c e r ­ emony. In many A frican an d Asian so cieties m arriages are a rra n g e d betw een teen ag e b rid e s an d grooms b y p a re n ts often with th e a ssista n c e of th ir d - p a r ty m arriage b ro k e rs . A fter th e m arriage cerem ony th e b rid e joins th e household o f th e groom 's p a re n ts w here sh e is in a sen se 'on p ro b atio n ' u n til th e b ir th of h e r f ir s t child w hereupon sh e becom es a fully accepted member of th e p a re n ta l family and household. In th e se circu m stan ces th e ru le s an d co n v en tions of m arriage a re clearly d eterm in ed , e v ery o n e know s w hat is ex p e cte d o f them and deviation is ex cep tio n al. In W esternised societies m arriage has th e same re p ro d u c tiv e an d legitim ising fu n c tio n s, b u t th e arran g em en t of m arriage is fa r more h a p h a z a rd . H ere th e r e is a balance betw een th e choices of in d iv id u a ls, and th e con­ s tr a in ts imposed by p a r e n ts an d society in g e n e ra l. T he social norms involved re la te to san ctio n s a g a in st n o n -m a rry in g couples an d th e u se of a family o rie n ta te d ideal as a means of giving m eaning to human e x iste n c e . In d iv id u al choice, on th e o th e r h a n d , in flu en ces th e age at which m arriage o c c u rs , th e p a r tn e r selected and th e d u ra tio n of th e m arriag e. For the dem ographer it is th e age at m arriage and th e p ro p o rtio n of th e p o p u latio n , especially fem ale, m arried in any one age group th a t is of most in te r e s t since th e se elem ents may have im portant e ffe c ts on fe rtility p a tte r n s p a rtic u la rly w here family lim itation is not in use (Woods an d H inde, 1985). But th e population g e o g ra p h e r may also be co n cern ed w ith contact p a tte rn s an d inform ation field s ( P e r r y , 1969; Morrill and P itts, 1967). Any m icro-theory of m arriage will need to contain two elem ents: se a rc h and selectio n . Let u s su p p o se th a t once an indiv id u al becomes eligible (a t 18 y e a rs p e rh a p s ) he o r she will e n te r th e s e a rc h c a teg o ry which co n tain s p a ssiv e an d active s e a rc h e rs (th e p ro p o rtio n of th e la tte r in c re a sin g with a g e ). The se a rc h will its e lf be a ffected by o p p o rtu n itie s, such a s th e sex ra tio am ongst elig ib les which is demographically d eterm in ed , an d b y th e s tr u c tu r e of d a y -to -d a y contact p a tte r n s which a re larg ely conditioned by a s e a r c h e r's re sid e n tia l, employment an d re c re atio n a l c h a ra c te ris tic s . Mutual selectio n , on th e o th e r h a n d , will be in flu en ced by perceiv ed com patibility on a num ber of levels (p h y sic a l, e d u ­ catio n al, in te r e s ts , family b a c k g ro u n d , fo r exam ple). T he decision to m arry will th u s re p re s e n t th e culm ination o f a p ro c e ss of se a rc h an d selection which at e v e ry sta g e biases the outcome tow ards th e p a irin g of m irro r im ages. B ut m ar­ riage also r e p re s e n ts a calcu lated decision to d e sist from f u r th e r s e a rc h , to cap italise on p r e s e n t a d v an tag e r a th e r th a n seek in g fo r additional gain in th e fu tu r e (see B e c k e r, 1981). Viewed in th is way m arriage and m igration will be seen as m anifestations of re la te d phenom ena which can be u n d e r­ 22

T H E O R Y AND M E T H O D O L O G Y IN P O P U L A T I O N G E O G R A P H Y

stood w ith in th e c o n te x t o f c o n s tra in e d ch o ice. T h e a c to rs a re ra tio n a l to a d e g r e e , th e y b a se th e ir d e cisio n s on sp ecific c rite ria w hich a lth o u g h th e y may n o t be a r tic u la te d a re re v e a le d b y p re f e r e n c e p a t t e r n s , b u t th e y m ust deal w ith b o th a lim ited a p p re c ia tio n o f th e p r e s e n t an d an in a d e q u a te know ledge o f th e f u tu r e . T h e s e a rc h is b ia se d a n d th e se lec ­ tion fa u lty . L evels: M id d le -ra n g e T h eo ry It h a s a lre a d y b een n o te d th a t m id d le -ra n g e th e o ry te n d s to deal in a g g r e g a te s , w ith th e c h a r a c te r is tic s of g ro u p s o f people v a rio u sly com bined. R ic h a rd A E a s te rlin 's (1969, 1971, 1978; E a s te rlin , Poliak a n d W achter, 1980) atte m p t to reco n cile economic a n d sociological th e o rie s of f e r tility in to one com­ po site th e o ry p ro v id e s an in te r e s tin g illu s tr a tio n of w hat may be a tte m p te d w ith th is lev el of c o n c e p tu a lisa tio n . E a ste rlin draw s from econom ics th e n o tio n th a t th e n u m b e r o f c h ild re n b o rn may be a m a tte r o f p a r e n ts b a la n c in g c o s ts a n d r e t u r n s ; th a t w hen th e s u p p ly of c h ild re n e x c e e d s th e dem and th e n th e u se of m eans to re d u c e th e n u m b er of ad d itio n a l u n w a n te d b ir th s will be a ffe c te d b y th e c o s ts of family lim itatio n . T he su p p ly of c h ild re n is ta k e n to b e b io logically d e te rm in e d , b u t b e c a u se E a ste rlin (1978) mainly d e a ls w ith s u rv iv in g c h ild re n h is form ulation is a ffe c te d b y c h a n g e s in in fa n t a n d child m o rtality . T h e dem and fo r c h ild re n will b e re la te d to social norm s (c h ild re n h a v in g a v alu e fo r t h e i r own s a k e ) , b u t also th e ris in g c o s ts of r e a r in g ’h ig h q u a lity f c h ild re n (p ro lo n g e d ed u catio n e tc ) an d th e ir d im in ish in g v a lu e a s c o n tr ib u to rs to th e family econom y. E a ste rlin a r g u e s th a t in p re -m o d e rn so cieties th e r e will b e a h ig h dem and fo r c h ild re n a n d th a t it will ex ceed s u p p ly , b u t th a t w ith m o d ernisation su p p ly will ris e an d dem and will fa ll. E v en tu ally su p p ly will meet dem and as e ffe c tiv e m eans o f b i r t h c o n tro l b o th becom e c h e a p e r and a re u s e d to avoid u n w a n te d b i r t h s . E a ste rlin (1971) u s e d a sim ilar th e o re tic a l fram ew ork to ta c k le th e q u e s tio n , does hum an fe r tility a d ju s t to th e e n v iro n m en t? H ere th e e n v iro n ­ ment is d iv id e d in to th r e e : th e f r o n tie r , s e ttle d r u r a l com­ m unities a n d u rb a n com m unities. T h e p re d ic tio n is th a t f e r ­ tility will b e h ig h e s t on th e f r o n tie r w h ere th e dem and for c h ild re n a s a so u rc e of a d d itio n a l la b o u r will b e h ig h e s t and th e m eans of a ffe c tin g fe rtility le a s t a c c e s s ib le , w h ilst in th e u rb a n a re a s fe r tility will be a t i t s low est fo r th e r e c h ild re n will not b e in s u c h dem and a n d m eans of b ir th c o n tro l a re lik ely to b e more a v a ila b le . T h e s e ttle d r u r a l com m unities a re th o u g h t to o ccu p y an in te rm e d ia te p o sitio n along th e con­ tin u u m . B roadly s p e a k in g , E a ste rlin fin d s th a t h is p re d ic tio n s a re b o rn e o u t in n in e te e n th - c e n tu r y m id -w est A m erica. T h e re a re two im p o rta n t p o in ts h e r e . F ir s t, E a ste rlin draw s from an e x is tin g , well e s ta b lis h e d th e o re tic a l fram ew ork 23

T HEO RY AND METHODOLOGY IN P O P U L A T IO N G EOGRAPHY

p rin c ip le s which he ap p lies to a p a rtic u la r c a se , a g g re g a te dem ographic b e h a v io u r. S econd, th e th e o ry so c o n stru c te d yields em pirically te sta b le h y p o th e se s (fe rtility will be h ig h e r/ lower in x when y holds e tc ) which make th e th e o ry fa lsifiable. T hese re p re s e n t two sig n ifican t a sp e c ts o f m iddleran g e th e o rie s. M iddle-range th e o rie s will of n e ce ssity have to face a num ber of common pro b lem s, ho w ever. Most o f th e se relate to v alid atio n , b u t some also o c c u r b ecause g ro u p s of people, o r a re a s a re u sed as re fe re n c e u n its . For exam ple, th e ecological fallacy and th e problem of eq u ifin ality b o th delimit formal te s tin g p ro c e d u re s . D espite th e se o fte n ob scu red draw b ack s m id d le-ran g e th e o ry re p re s e n ts th e most commonly employed level of th e o re tic a l dev ice. A dditional exam ples will be d isc u sse d below (u n d e r 2 ). Levels: G rand T heory Amongst population g e o g ra p h e rs th e most widely u sed g ra n d th e o ry is u n d o u b ted ly th a t of th e dem ographic tra n s itio n . In its original form , as conceived b y F. W. N otestein (1945), th e th eo ry had d istin c t se c tio n s. T he f ir s t com prised a d e s c rip ­ tion of th e dem ographic situ atio n in p re -S e c o n d World War Europe and Am erica. The second sk e tc h e d ch an g es in b ir th and d eath ra te s such th a t b o th w ere in itially h ig h , death ra te s fell while b ir th r a te s rem ained h ig h , and fin a lly , b irth ra te s fell to match d eath ra te s a t low lev els. T he th ird defined th re e sta g e s in term s o f population grow th ra te s : slow, ra p id and slow. The fo u rth an d final section p ro p o sed an e x p lan ato ry mechanism (a g ric u ltu ra l, in d u s tria l a n d sa n i­ ta ry rev o lu tio n s) which fo rced m ortality down and ultim ately, via th e sp re a d of c o n tra c e p tio n , rem oved th e p ro p s to high fe rtility . In su b se q u e n t reform u latio n s N o testein 's th e o ry has been e n la rg e d an d made more flex ib le, b u t it still re ta in s its basis in h isto rical an alo g y , its th re e sta g e s and its in siste n c e th a t dem ographic ch an g e re s u lts from cum ulative socio­ economic ad v an ces (o ften term ed m o d ern isatio n ). All form s of tra n sitio n th e o ry , w h e th e r o rig in al o r re v is e d , deal with long-term change in th e e n tire dem ographic system which th e y re g a rd as a consequence of sig n ifican t c h an g es in th e econ­ omic technological an d political o rd e rin g of so cie ty . T he fam­ ilia r re p re se n ta tio n of th e th e o ry in model form (time se rie s fo r b ir th an d d e a th ra te s ) an d th e in e v ita b ility w ith which successive p opulations re p lic a te its g e n e ra l shap e h av e given th e e x p lan ato ry section of th e th e o ry an im m ortality which is no lo n g er d e se rv e d (se e Woods, 1979, 6 ). T h ere a re th re e re a so n s fo r ta k in g th is view . F irs t, dem ographic tra n s itio n th e o ry may be said to be too g e n e ra l, it lacks th e specificity of a m id d le-ran g e th e o ry and is th u s difficult to e v a lu a te . Second, th e re is no mechanism w ithin th e th e o ry th a t will g e n e ra te th e se q u e n tia l movement betw een sta g e s (3 m ust follow 2, 2 m ust follow 1 ). T h ird , and p e rh a p s 24

T HEORY AND METHODOLOGY IN P O P U L A T IO N G EOGRAPHY

of most im po rtan ce, th e u se of h isto ric a l analogy is likely to provide a fau lty logic (w hat will h ap p en in x will hap p en in y ). It is now obvious th a t th e dem ography of h isto ric al societies was b o th more v a rie d a n d more complex th a n had been p re v io u sly been th o u g h t; th a t p a rtic u la r c u ltu re s w ere likely to have th e ir own specific dem ographic regim es; and th a t dem ographic e x p e rie n c e m ight not be c u ltu ra lly tr a n s f e r ­ able. For exam ple, it a p p e a rs th a t economic developm ent coupled w ith a d m in istrativ e o rg a n isa tio n w ere mainly re sp o n ­ sible fo r in itia tin g th e se c u la r decline of m ortality th a t b egan in Europe and N orth America in th e la te n in e te e n th c e n tu r y , b u t in Latin Am erica, Asia an d A frica, w here m ortality has fallen it h as done so la rg e ly v ia th e in tro d u c tio n of European and American technological e x p erien ce (esp ecially in term s o f medical scie n c e , chem otherapy an d p u b lic h ea lth ) a n d h a s not necessarily been linked w ith economic g ro w th . In Europe th e fall in child th e n in fa n t m ortality te n d e d to re in fo rc e th e need for and a d v a n ta g e s of family lim itation, b u t th e su d d e n fall in m ortality am ongst most T h ird World so cieties could only lead to ra p id population grow th since n u p tia lity and m arital fe r­ tility w ere incapab le of a d ju s tin g so q u ick ly to su c h dram atic changes in th e absen ce of re q u ire d social and economic d ev el­ opm ents. T he su b se q u e n t fall in m arital fe rtility w hich has been o b se rv e d am ongst p o p u latio n s in L atin America an d c e r­ tain p a r ts of Asia (especially th e islan d s ta te s ) re la te s not only to th e e ffe c ts of u rb a n -in d u s tria l g ro w th , b u t also th e v ario u s family p lan n in g program m es in tro d u c e d w ith g o v e rn ­ ment s u p p o rt and W estern en co u rag em en t. In C hina th e fe r­ tility tra n s itio n is b e in g p lan n ed in d e p e n d e n tly of m odern­ isatio n . (T h e re is a volum inous lite r a tu r e on th e se is s u e s , b u t Caldwell, 1982, B ulatao an d Lee, 1983; Woods, 1982, p ro v id e in tro d u c tio n s .) One way to b eg in th e developm ent o f a g ra n d th e o ry of dem ographic b e h a v io u r would b e to a rg u e in term s of th e fa c to rs th a t cou ld , in a b s tr a c t, in flu en ce dem ographic s tr u c tu r e s . T he following p ro v id e s an exam ple. A.

F acto rs th a t will te n d to re d u c e m ortality 1. A dvances in medical an d d r u g technology 2. Economic developm ent 3. More eq u itab le income d is trib u tio n 4. Im proved q u a n tity an d q u ality o f food su p p ly 5. Im proved q u a lity of w ater su p p ly 6. E ffective local an d national governm ent 7. Im proved ed u catio n (especially h e a lth ed u catio n ) 8. Political sta b ility

B.

F acto rs th a t will te n d to re d u c e m arital fe rtility 1. The availability of effe c tiv e c o n tra c e p tiv es 2. U rbanisation 3. In d u stria lisa tio n 4. Im proved ed ucation (especially fo r women) 5. R ising social s ta tu s of women 25

T HEORY AND METHODOLOGY IN P O P U L A T IO N GEOGRAPHY

6. 7. 8.

Decline in in fa n t an d child m ortality R e stric tio n s on th e economic v alu e of ch ild re n R ising liv in g s ta n d a rd s

A lthough many of th e se fa c to rs a re a sso c ia te d , ch ange in each one is capable of e ffe c tin g a n eg a tiv e c h an g e in m ortality o r marital fe rtility . D em ographic tra n s itio n th e o ry c o n sists o f a fixed list of fa c to rs which a re th o u g h t to be u n iv e rsally a p p ro p ria te . The scheme p ro v id e d h e re h as a more flexible b a sis which allows for th e s u b stitu tio n of fa c to rs . For in s ta n c e , m arital fe rtility may be re d u c e d as a re s u lt of B1 + B4 in th e ab sen ce of B2 + B3. No one is on its own su fficie n t o r n e c e s sa ry , n o r is th e exclu sio n of a fa c to r in a p a rtic u la r case evidence fo r its irre le v a n c e elsew h ere. The function of g ra n d th e o ry in th is in sta n c e would be to e sta b lish th e lis ts of fa c to rs , to sp ecify th e associations involved (p o sitiv e o r n e g a tiv e ) an d to make clear how th e dem ographic v a ria b le s (m ortality and m arital fe rtility above) are them selves in te rre la te d in some total dem ographic system . It would be fo r middle ra n g e th e o ry to h y p o th e sise on th e fac to rs inv o lv ed in a p a rtic u la r case (C hina p o st 1949, n in e­ te e n th -c e n tu ry E urope e tc ) an d to ex p lo re th e em pirical v alid ­ ity of such h y p o th e se s. T he exam ples given above w ere in te n d e d merely to illu s ­ tra te some of th e more commonly reco g n ised problem s in th eo ry c o n stru c tio n an d to do so via in s ta n c e s draw n from population g eo g rap h y o r d em ography. F ig u re 1.2 also lis ts five p a rtic u la r m ethodologies which will co ntinue to have sig ­ nificance in g eo g ra p h y . T he rem ain d er of th is c h a p te r is devoted to a b rie f review of th e im portance and p o te n tial of each of th e se m ethodologies for th e stu d y of population by g e o g ra p h e rs. 1 Empiricism Both dem ography and population g eo g rap h y have been domi­ nated by m ethodology th a t is im plicitly em pirical. Much a tte n ­ tion has been given to th e d e sc rip tio n of p a tte r n , estim ation, modelling an d fo re c a stin g , b u t re la tiv e ly le ss to in te rp re ta tio n o r ex p lan atio n . S ta tistic a l d em o g rap h ers h ave developed effec­ tiv e estim ation p ro c e d u re s b ased on in a d e q u a te c e n su s o r v ital d ata w hilst population g e o g ra p h e rs have made a sig n ific an t co n trib u tio n to th e developm ent of m ulti-regional dem ographic acco u n tin g system s (see Woods an d R ees, 1986). Both re q u ire the c o n stru c tio n of formal m athem atical th e o rie s , b u t n e ith e r is immediately co n cern ed w ith th e ex p lan ation of dem ographic e v e n ts. G eo g rap h ers have also developed so p h istica te d te c h ­ niq u es fo r th e h an d lin g of sp atially o rg a n ised population d ata and especially th e ir u se in autom ated c a rto g ra p h y . Upon th is b a sis of m apping an d p lo ttin g , c o u n tin g and d esc rib in g r e s ts a complex web of re s e a rc h th a t employ one o r a num ber of o th e r m ethodologies. 26

T HEO RY AND METHODOLOGY IN P O P U L A T IO N GEOGRAPHY

2 Positivism When q u e stio n s of a cau sal n a tu re a re a d d re s s e d th e n some form of th e p o sitiv ist m ethodology is u su ally en g a g e d . Posi­ tivism c o v ers a num ber of v a ria n ts on th e same them e; b u t sup p o sed ly tr u e p ro p o sitio n s a re f ir s t s ta te d ex p licitly and th e n su b jected to close s c ru tin y o r te s tin g . A lthough the shortcom ings of th is ap p ro ach a re now rec o g n ised (some w ere mentioned above) th e a sp ira tio n s o f positivism ap p lied to th e human sciences a re laudable y e t bey o n d fu ll rea lisa tio n . In th e stu d y of population th is m ethodology h a s b e en p u t to good effect especially in th o se circu m stan ces th a t len d them ­ selves to causal modelling of a m u lti-v a ria te k in d . For exam ple, sp atial v a ria tio n s in m o rtality , fe rtility an d m igration have been re p eated ly tre a te d in th is w ay. Let u s tak e v a ri­ ations in fe rtility as o u r illu stra tio n . F e rtility levels will be d ire c tly in flu en ced b y m arital fe rtility , illegitim ate fe rtility an d th e p ro p o rtio n o f th e female population m arried . Each of th e se com ponents will b e affec ted by o th e r c u ltu ra l, economic, social, political an d dem ographic fac to rs whose association w ith th e d e p e n d en t com ponents o f fe rtility may be h y p o th e sise d and id e n tifie d em pirically in specific circum stance v ia th e co -v a ria tio n of fa c to rs and com ponents o v er sp atial u n its . Some o f th e fa c to rs in flu en cin g m arital fe rtility have a lre a d y been s u g g e s te d above (p 25). A su b sta n tia l num ber of e x istin g s tu d ie s follow th is line o f argum ent with v a ry in g d e g re e s of en lig h tenm ent (T eitelbaum , 1984; A n k er, 1978; Bagozzi and Van Loo, 1978; see also C adw allader, 1985 on m ig ratio n ). H ow ever, th e a tte n d a n t problem s are v e ry obvious. F ir s t, h y p o th e sis evaluation is u sually accom plished th ro u g h m u ltip le-reg ressio n a n a ly sis which allows th e sig n s and stre n g th s of association to be sp ecified , b u t d e p e n d s on the fa c to rs b ein g q u a n tifia b le . S econd, asso ciatio n s may b e u n ­ stab le when th e scale of an aly sis is a lte re d . T h ird , fa c to rs are likely to be h ighly in te r-d e p e n d e n t. F o u rth , th e co­ variatio n of sta tis tic a l a ttr ib u te s w hilst p ro v id in g a means of elim inating unlikely p ro p o sitio n s does not give an o p p o rtu n ity to tra c e many of th e more id io sy n c ra tic p ro c e sse s in v o lv ed in th e creatio n of dem ographic b e h a v io u r an d th u s p a tte r n s . P a tte rn an aly sis b y its e lf simply skim s th e su rfa c e o f w hat is o bserv ab le an d m easu rab le, it does not re la te well to th o se a sp e c ts which may be in ta n g ib le y e t o f deep sig n ifican ce. D espite th e se in h e re n t d raw b ack s cau sal modelling h a s been used to some effect in population s tu d ie s . S everal forms of positivism will rem ain im p o rtan t in population g eo g rap h y an d d em ography, b u t now th e r e is fa r more realism about th e scope of th e m ethodology, its red u c tio n ist n a tu re and th e p o te n tia l of a lte rn a tiv e ap p ro ach es.

27

THEORY AND METHODOLOGY IN P O P U L A T IO N G EOGRAPHY

3, 4 & 5 B ehaviouralism , Humanism an d S tru ctu ralism F igure 1.2 list th re e of th e se a lte rn a tiv e ap p ro ac h e s: b e h a v ­ iouralism , humanism an d s tru c tu ra lis m . A lthough th e y a re all commonly u se d in hum an g eo g ra p h y s tu d e n ts of population have b een less a d v e n tu ro u s in ex p erim en tin g w ith them th a n one might have e x p e c te d . T he b eh av io u ral app ro ach h as c e r ­ tainly p ro v e d of v alu e fo r th e stu d y of m igration decision making and p ro b ab ly h as equ al p o te n tia l in u n scram bling th e sequence of d ecisions invo lv ed in m arriage and family form a­ tion . Its ch ief failings re la te to th e p relim inary assum ption of ratio n al human b e h a v io u r an d th e d e g re e to which th e a tti­ tu d e s and b e h a v io u r of in d iv id u a ls a re th o u g h t to be d e te r ­ minable (see Cox an d G olledge, 1981). T his methodology does at least move th e r e s e a rc h e r c lo se r to p ro c e ss recognition by focusing on m otivation an d not ju s t p a tte rn -fo rm . Humanistic geo graphy attem p ts a lo n g e r jo u rn e y to w ards th e ex p erien ce of in d iv id u als via 'th e u n d e rs ta n d in g of humain action th ro u g h th e stu d y of m eanings allocated to th e elem ent of th e in d iv id ­ u a l's life-w orld' (J o h n sto n , 1983, 5 7 ). T he r e s e a rc h e r is obliged to im agine th a t w hich th e in d iv id u al ex p e rie n c es and to asso ciate w ith it not h is o r h e r own m eaning, b u t th a t of th e object of s tu d y . The e x e rc ise is d e lib erate ly su b je c tiv e , th e re is no attem p t a t p r io r h y p o th e sis o r e x p lan a tio n , u n d e r­ sta n d in g an d in te rp re ta tio n a re th e go als. Amongst geo­ g ra p h e rs in g en eral th e hum anistic ap p ro ac h has been most widely developed in lan d scap e s tu d ie s , w here its m eaning is in te rp re te d from th e in h a b ita n t's p e rs p e c tiv e , an d in u rb a n social g e o g ra p h y , w here p a rtic ip a n t o b se rv a tio n o ffe rs some p ro sp e c t of illum ination (see Lowenthal 1961; Ley and Sam uels, 1978; Ja c k so n , 1983). T h ese m ethods will also be a p p ro p ria te to u n d e rs ta n d re a c tio n s to dem ographic e v e n ts (a rra n g e d m a rria g e s, re p e a te d p re g n a n c ie s e tc ) th ro u g h th e feelings of th o se in d iv id u als who a re d ire c tly in v o lv ed . How do C hinese p e a s a n ts re sp o n d to th e o n e-ch ild family policy? What do unem ployed Scots feel about m ig ratin g to London? What is th e m eaning of ch ild re n fo r th e Indian family? All of th e se q u e stio n s may be tack led via th e hum an­ istic m ethodology. Yet once again th e re a re c e rta in d iffic u lt­ ie s. F ir s t, th e r e s u lts o b tain ed b y th e r e s e a rc h e r will n o t be replicable in th e se n se th a t p o sitiv ist a n a ly sis may be r e p ro ­ d u ced . Second, th e level of u n d e rs ta n d in g o b ta in e d , w hilst in one sen se d e e p , will not tr a n s f e r easily to th e p ra c tic a l req u irem en ts of p la n n e rs an d fo re c a s te rs . T h ird ly , th e re is little agreem ent on ex actly w hat p ro c e d u re s a r e to b e followed, th e in v e s tig a to r is left to h is o r h e r own in tu itio n in th e se a rc h fo r self-k n o w led g e. T h ese a re im portant problem s, y e t more could be le a rn t from th is a p p ro a c h which would sh e d light on th e com plicated p ré c ip ita n ts of actio n . T he la st methodology m entioned in F ig u re 1.2 is s tr u c ­ tu ralism . Again th e re is no sin g le a g re e d d e fin itio n , r a th e r th e ap p ro ach h as been given a label th a t co v e rs a n u m ber of 28

T HEO RY AND METHODOLOGY IN P O P U L A T IO N G EOGRAPHY

d ifferen t n u an ces of opinion. One c e n tra l them e, how ever, re fe rs to th e significance of c o n s tra in ts on human action which b o th limit an d enable c e rta in b e h a v io u r p a tte r n s to em erge. In th e M arxist tra d itio n th e s tr u c tu r e o f so ciety is conditioned b y th e dom inant mode o f p ro d u ctio n an d its related social form ation (C a rv e r, 1982). T he b e h a v io u r of individuals is not a m atter of free will, r a th e r th e form o f society im poses c o n s tra in ts an d o b lig atio ns w hich se v erely limit choice. B ehaviour is not d e te rm in ed , how ever. The org an isatio n of th e c ap italist sy stem , fo r exam ple, re q u ire s w orkers to sell th e ir la b o u r pow er to th e ow ners o f th e means o f p ro d u ctio n fo r w ages; it is b a sed on th e p riv a te ow nership of p r o p e r ty , an d com petition betw een p ro d u ctio n u n its , p ro d u c e rs an d em ployees. T hese re la tio n sh ip s in fluence all o th e r a sp e c ts of so c ie ty , in c lu d in g dem ographic b e h a v io u r. Marx was him self most co n cern ed to r e fu te th e n a tu ra l­ istic re p re se n ta tio n of dem ographic sy stem s which is to be found in M althus's p rin c ip le of p o p u latio n . In i t s place he ad v an ced , b u t did not e la b o ra te , th e id ea th a t each mode of pro d u ctio n (an cien t s la v e ry , feudalism , capitalism , socialism , Asiatic) would have its own p a rtic u la r ’law of p o p u latio n 1. U nder capitalism th e re is need fo r an ’in d u s tria l re s e rv e arm y’ th e relativ e size of which will b e in v e rse ly re la te d to wage r a te s . The 's u r p lu s pop u latio n ' so g e n e ra te d will com­ p rise th e p o o rest section of so c ie ty , th e one su b jec te d to th e hig h est d eath r a te s , b u t th e one h av in g th e h ig h e st fe rtility (Woods, 1983, 1986). A lthough M arx's concept of h isto ric a l materialism p ro ­ vides th e most clearly a rtic u la te d b a sis fo r a s tr u c tu r a lis t approach (as seen in H arv ey , 1973) sc h o la rs of M arxian social th e o ry a re much p reo ccu p ied by th e in te rn a l te n sio n s th a t ex ist betw een th e d e s ire s of in d iv id u als a n d th e n e ed s of society , an d th u s betw een th e life th a t in d iv id u als make for them selves an d th a t p re s c rib e d fo r them b y w ider social g ro u p in g s. The concept of s tru c tu ra tio n h a s been developed to reconcile some of th e se te n s io n s , in an in telle ctu a l se n se at le a st. G iddens (1984) h a s a rg u e d for a com bination of hum an­ istic concep ts w ith th o se of a more form alised stru c tu ra lism so th at in d iv id u als' actio n s would a p p e a r conditioned by th e s tru c tu ra l c o n tex t w ithin which th e y fin d th em selv es, b u t th ey would also be capable of ac tin g to c h an g e th a t c o n tex t and not m erely re a c tin g to i t . Human ag en cy would b e given an im portant role in a ffe c tin g 'life -w o rld ', b u t th a t se t o f relatio n sh ip s an d m eanings would also have a d e e p e r sig n ifi­ cance em anating from th e way in which society a s a whole is o rd e re d . The scep tic may see th is m erely as an accommodation betw een a naive idealism and an o v e r-rig id m aterialism . Yet th e re a re good re a so n s fo r a more p o sitiv e re sp o n se , especially from population g e o g ra p h e rs, who a re concerned with b o th explanation an d u n d e rs ta n d in g , sp atia lly a rtic u la te d social c o n s tru c ts an d in d iv id u al decision m aking. T he impli­ 29

THEORY AND METHODOLOGY IN P O P U L A T IO N GEO GR A PHY

cations fo r em pirical re s e a rc h rem ain u n c le a r, as y e t, b u t th e re a re some slig h t sig n s o f re o rie n ta tio n am ongst some p ra c titio n e rs of th e more single-m inded a p p ro ac h es (see Woods, 1985, fo r ex am p les). BACKWARDS AND FORWARDS The th e o rie s an d m ethodologies sk e tc h e d above p ro v id e exam ples of some of th e id e a s c u rre n tly in vogue am ongst social s c ie n tists whose co n cern is w ith p o p u latio n . Each of th e app ro ach es h as a d v a n ta g e s and lim itations, none o ffe r even th e p ro sp e c t of com plete ex p lan atio n o r u n d e rs ta n d in g y e t none can b e ig n o re d . T h is p lu ra lity of a p p ro ac h es is only to b e welcomed, it re fle c ts a h e te ro d o x y , a m ethodological g ard en of d e lig h ts. T h e re is no lo n g e r any need fo r e c le c ti­ cism, choosing th e ap p ro ach to su it th e q u e stio n , a problem may be tack led u sin g a num ber of a p p ro a ch e s each one of which will sh ed new lig h t from a d iffe re n t p e rs p e c tiv e . Nor is th e re need for com petition betw een m ethodologies since each will w ork to it s own epistem o lo g y . T he th r e e levels of th e o ry outlined e a rlie r will also te n d to complement one a n o th e r. F or th e population g e o g ra p h e r a num ber of v e ry s u b ­ stan tial problem s do rem ain, how ever. 1.

2.

3.

30

How should popu latio n g eo g rap h y be defined? T his is an im p o rta n t, alth o u g h ted io u s q u e stio n . T h is c h a p te r ad v o cates th e u se of a narrow d e fi­ nition which em phasises th e d iffe re n c es betw een hum an, u rb a n and population g e o g ra p h y . T he last m entioned h a v in g an in n e r core which s tr e s s e s sp atial v a ria tio n s in m o rta lity , fe rtility and m igration, an d th u s th e d is trib u tio n an d s tr u c tu r e of population. How may th e influ en ce of population g eo g rap h y be ad v anced w ithin g eo g rap h y an d in population stu d ie s in general? The la tte r will be accom plished when g e o g ra p h e rs adopt dem ographic te c h n iq u e s; p e rsu a d e demo­ g r a p h e r s , b y exam ple, of th e v alu e of p o s t-p o sitiv ist ap p ro ach es; and red u c e th e ir p reo ccu p atio n w ith m igration. T he form er would be enhan ced b y the co n cen tratio n of e ffo rt on p a rtic u la r q u e stio n s (1 a b o v e ), th e developm ent o f consciously th eo re tic al a n a ly se s; and th e adv an ce of m odelling, fo rec astin g an d d a ta h a n d lin g /d isp la y te c h n iq u e s (th e 'u se fu l know ledge' a p p ro a c h ). What s u b s ta n tiv e q u e stio n s rem ain u n an sw ered in population s tu d ie s th a t could b e tackled b y geo­ g ra p h e rs?

T HEO RY AND METHODOLOGY IN P O P U L A T IO N GEOGRAPHY

O bviously th e re a re a num ber of is s u e s b u t th r e e will be m entioned h e re b y way of illu s tra tio n . F ir s t, th e re is as y e t no com prehensive th e o ry of m igration which com bines th e o re tic a l levels and m ethodologies (in d iv id u als g ro u p s , cau sal models - hum anistic in te r p re ta tio n s e tc ) . Yet h e re is an area in which em pirical r e s e a rc h by geo­ g ra p h e rs h as b een fru itfu l and is most a b u n d a n t. S econd, th e sp atial v a ria tio n s in contem porary demo­ grap h ic regim es betw een c u ltu ra l re g io n s rem ain only p artially u n d e rsto o d w hilst th e ir h isto ric a l developm ent has larg ely b een ig n o re d o u tsid e E urope an d America. T h ird , th e application of fo re c a stin g m ethods via geo­ g rap h ical data b a se s to iss u e s of environm ental m anage­ m ent, h o u sin g policy and social p la n n in g h a s c o n sid e r­ able u n re a lise d p o te n tia l to which population g e o g ra p h e rs can c o n trib u te th e ir sk ills. T h ere need be no com placency re g a rd in g p a st achievem ents nor confusion of fu tu re p u rp o s e ; population g e o g ra p h e rs have im portant c o n trib u tio n s to make to th e ir te a c h in g su b je c t, th e ir re se a rc h d iscipline an d to closely re la te d d iscip lin es, especially dem ography. REFERENCES A n k er, R. (1969) 'A n A nalysis o f F e rtility D ifferen tials in D eveloping C o u n trie s ', Review of Economics an d S ta t­ i s tic s , 60, 58-69 B agozzi, R .P . and van Loo, H .F . (1978) ’Tow ards a G eneral T heory of F e rtility : A C ausal Modelling A pproach’, D em ography, 15, 301-319 Bahe] J . (1983), B ev ö lk eru n g in G lobaler, N ationaler u n d R egionaler S ic h t, V erlag Eugen Ulmer, S tu ttg a r t B eck er, G .S . ( 19Ö1) A T re a tise on th e Fam ily, H arv ard Uni­ v e rs ity P re s s , C am bridge, Mass B e rry , B .J .L . (1967) G eography of M arket C e n te rs a n d Retail D istrib u tio n , P re n tic e -H a ll, Englewood C liffs, NJ B e rry , B .J .L . an d H orton, F .E . ( e d s .) (1970) G eographical P e rsp e c tiv e s on U rban S y stem s, P ren tice-H all, Englewood C liffs, NJ B ulatao, R .A . an d Lee, R .D . ( e d s .) (1983) D eterm inants of F ertility in D eveloping C o u n tries (2 vo lu m es). Academic P re s s , New York C adw allader, H. (1985), ’S tru c tu ra l E quation Models of M igration: An Example from th e U p per Midwest USA’ , E nvironm ent an d Planning A , 17, 101-113 Caldwell, J .C . (1982) T h eo ry of F e rtility D ecline, Academic P re s s , London

31

THEORY AND METHODOLOGY IN POPULATIO N GEOGRAPHY

C arv er, T . (1982) M arx's Social T h e o ry , O xford U niversity P re ss, Oxford C larke, J . I . (1965, second edition 1972) Population Geo­ g ra p h y , Pergam on, O xford C larke, J . I . (1977) 'Population G eography', P ro g ress in Human G eography, 1, 136-141 Clarke^ J . I . (1978) ' Population G eography', P ro g ress in Human G eography, 2, 163-169 Clarke^ J . I . (1979) 'Population G eography', P ro g ress in Human G eography, 3, 261-266 Clarke") J . I . (1980) 'Population G eography', P ro g ress in Human G eography, 4, 385-391 C larke, J . I . (1984) 'G eography, Demography and Population' in J . I . Clarke ( e d .) Geography and Population, 1-10, Pergamon, Oxford Cox, K .R . and Golledge, R .G . (e d s .) (1981) Behavioral Problems in G eography R ev isited , M ethuen, London D esb arats, J .H . (1981) 'C o n strain ed Choice and M igration', G eografiska A nn aler, 658, 11-22 EasterUnT R.A . (1969) 'T ow ards a Socioeconomic T heory of F ertility : A Survey of Recent R esearch on Economic F actors in American F e rtility ', in S .J . Behrman et al. ( e d s .) . F ertility and Family Planning: A World View, 127-157, Michigan U niversity P re s s , Ann A rbor, Michigan E asterlin, R .A . (1971) 'Does Human F ertility Adjust to the Environm ent?' American Economic Review, Papers and P roceedings, 61, 399-407 E asterlin, R .A . (1978) 'T he Economics and Sociology of F er­ tility : A S yn th esis' in C. Tilly ( e d .) , Historical Studies of Changing F e rtility , 57-133, Princeton U niversity P re ss, P rinceton, NJ E asterlin, R .A ., Poliak, R .A . and W achter, H .L. (1980) 'Tow ard a More General Economic Model of F ertility D etermination: Endogenous P referen ces and N atural F er­ tility ' in R .A . E asterlin ( e d .) , Population and Economic Change in Developing C o u n trie s, 81—135, Chicago Uni­ v e rsity P re ss, Chicago G iddens, A. (1984) The C onstitution of S ociety, Polity P re ss, Cambridge Greenwood, H .J. (1981) Migration and Economic Growth in the United S ta te s , Academic P re ss, New York H arvey, H.W. (1973) Social Ju stice and th e C ity , Edward A rnold, London Jackson, P. (1983) 'P rinciples and Problems of P articipant O bservation', G eografisk A n n aler, 658, 39-46 Johnston, R .J . (1983) Philosophy and Human G eography, Edward A rnold, London Jones, H .R . (1981) A Population G eography, H arper and Row, London

32

T HEO RY AND METHODOLOGY IN P O P U L A T IO N G EOGRAPHY

K osinski, L .A . (1984) 'T h e Roots of P opulation G eography' in J . I . C larke ( e d . ) , P opulation an d G e o g ra p h y , 11-24, Pergam on, O xford L eibenstein, H. (1976) B eyond Economic Man, H arv ard Uni­ v e r s ity P re s s , C am bridge, Mass Ley, D. an d Sam uels, H .S . ( e d s .) (1978) H um anistic Geo­ g ra p h y , Croom Helm, London L ieber, S .R . (1978) 'P lace U tility an d M ig ration', G eografiska A n n a le r, 608, 16-27 Low enthal, t). (1961) 'G e o g ra p h y , E x p erience a n d Im agin­ atio n : T ow ards a G eographical E pistem ology', A nnals of th e A ssociation of American G e o g ra p h e rs, 51, 241-260 M erton, R .K . (1967) On T h eo retical Sociology, F ree P re s s , New York M orrill, R .L . and P itts , F .R . (1967) 'M arriag e, M igration and th e Mean Inform ation F ie ld ', A nnals o f th e A ssociation o f American G e o g ra p h e rs, 57, 401-422 Newman, J .L . and M atzke, GTE. (1984) Population : P a tte r n s , Dynamics and P ro s p e c ts , P ren tice Hall, Englewood C liffs, NJ Noin, D. (1979) G éographie de la P o p u latio n , M asson, P aris Noin, D. (1984) Ee Champ d 'E tu d e s de” la D ém ographie', E space, P o p u latio n s, S o c ié té s, 2 ( 2 ) , 65-70 N otestein, F.W. (1945) 'P opulation: T he Lone View' in T .H . Schultz ( e d .) Food for th e W orld, 36-57, Chicago Uni­ v e rs ity P re s s , Chicago P e rry , P .J . (1969) 'W orking C lass Isolation and Mobility in R ural D o rset, 1837-1936: A S tudy o f M arriage D ista n c e s', T ra n sa c tio n s, In s titu te of B ritish G e o g ra p h e rs, 461, liS -lS S P ry o r, R .J . (1984) 'M ethodological Problem s in Population G eography' in J . I . C larke ( e d . ) , G eography and Popu­ lation , 26-42, Pergam on, O xford R hind, D. ( e d .) (1983) A C ensus U se r's H andbook, M ethuen, London S k in n e r, Q. ( e d .) (1985) The R e tu rn o f G rand T h eo ry in th e Human S cie n c e s, C am bridge U n iv ersity P r e s s , C am bridge S p eare, A. (1971) 'A Cost B enefit Model o f R ural to U rban M igration in T aiw an', Population S tu d ie s , 251, 117-130 T eitelbaum , M .S. (1984) T he B ritish F e rtility D ecline, P rinceton U n iv ersity P r e s s , P rin c e to n , NJ T re w a rth a , G .T . (1953) 'A Case fo r Population G e o g ra p h y ', A nnals of th e A ssociation of Am erican G e o g ra p h e rs, 43, W ebber, H .J . (1972) Impact of U n c e rta in ty on L ocation, MIT P re s s , C am bridge, Mass White, P .E . (1981) 'M igration a t th e M icro-scale: I n tra parochial Movements in R ural N orm andy, 1946-54', T ra n sa c tio n s, In s titu te of B ritis h G e o g ra p h e rs, New S eries, 6, 451-470 33

THEORY AND METHODOLOGY IN POPULATIO N GEOGRAPHY

White, P.E . and Woods, R .I. ( e d s .) (1980) The Geographical Impact of M igration, Longman, London Wolpert, J . (196i) 'T he Decision Process in a Spatial Con­ te x t' , Annals of the Association of American Geo­ g ra p h e rs , 541, 537-558 Wolpert, J . (1965) 'B ehavioural A spects of th e Decision to M igrate', Papers and Proceedings of th e Regional Science A ssociation, 15, 159-169 Wolpert, J . (1966) 'M igration as an Adjustment to E nviron­ mental S tr e s s ', Jo u rn al of Social I s s u e s , 22, 92-102 Woods, R .I. (1979) Population A nalysis in G eography, Longman, London Woods, R .I. (1982) T heoretical Population G eography, Longman, London Woods, R .I. (1983) 'On th e Long-term R elationship Between Fertility and the S tan d ard of L iving', G enus, 39, 21-35 Woods, R .I. (1985) 'Population S tu d ie s', P ro g ress in Human G eography, 9, 278-282 Woods, R .I. (1986) M althus, Marx and Population C rises' in R .J . Johnston and P .J . Taylor ( e d s .) , A World in C ris is , 127-149, Blackwell, O xford Woods, R .I. and Ilinde, P .R .A . (1985) 'N uptiality and Age at M arriage in N in eteen th -cen tu ry E ngland', Journal of Family H isto ry , 10, 119-144 Woods, R .I. and R ees, P.H . ( e d s .) (1986) Population S tru c ­ tu re s and Models, Allen and Unwin, London

34

C h a p te r Two THE BRITISH AND UNITED STA TES1 CENSUSES OF POPULATION J . C . D ew dney a n d D. R hind

INTRODUCTION Of all th e s o u rc e s of d a ta u se d in m odern p o p u la tio n geo­ g r a p h y , none is r ic h e r th a n th e n a tio n a l c e n s u s , w hich p ro v id e s a v a s t r a n g e of in fo rm atio n on th e p o p u la tio n ’s siz e , d is tr ib u tio n , s t r u c t u r e , liv in g c o n d itio n s a n d m ovem ents. T h e p ra c tic e o f c o u n tin g p eo p le h a s a le n g th y h is to r y , which e x te n d s b ack o v e r h u n d r e d s if not th o u s a n d s of y e a r s , b u t th e c e n s u s a s we know it to d a y is e s s e n tia lly a p ro d u c t of th e n in e te e n th a n d tw e n tie th c e n tu r ie s . E a rlie r c o u n ts w ere c a rrie d o u t by a u th o r itie s w ith some sp e c ific p u rp o s e in m ind, su c h a s ta x a tio n o r m ilitary c o n s c rip tio n , w ere u su a lly con­ fin ed to a p a r tic u la r se c tio n o f th e p o p u la tio n - most commonly a d u lt males - an d w ere n e v e r p u b lis h e d in fu ll. T h e m odern c e n s u s h a s b e e n d e fin e d (U n ite d N atio n s, 1967) a s " th e to ta l p ro c e s s of c o lle c tin g , com piling, e v a lu ­ a tin g , a n a ly s in g a n d p u b lis h in g d e m o g rap h ic, econom ic an d social d a ta p e r ta in in g , a t a sp e c ifie d tim e, to all p e r s o n s in a c o u n try o r in a w ell-delim ited p a r t of a c o u n tr y ." T h is im­ p lies an o ffic ia l, g o v ern m en tal activ ity » a co m p reh en siv e co v e ra g e of th e e n tir e p o p u la tio n an d th e p u b lic a tio n o f a se t of d a ta r e f e r r in g to a sp e c ific p o in t in tim e. Also im plicit is th e id ea th a t a c e n s u s sh o u ld b e one of a r e g u la r s e r ie s , th o u g h th is d e s ira b le s itu a tio n h a s so f a r b ee n a c h iev e d in only a m inority of c o u n tr ie s , in c lu d in g th e U nited K ingdom . The m odern c e n s u s in v o lv e s m uch more th a n a sim ple h e a d ­ co u n t an d th e p u b lic a tio n of to ta l n u m b e rs: it also in v o lv es th e collection a n d p u b lic a tio n of in fo rm atio n on many of th e c h a r a c te r is tic s o r ’a t tr i b u t e s ’ of th e in d iv id u a l, su c h as h is /h e r s e x , a g e , m arital s t a t u s , b ir th p la c e , economic a c ­ tiv ity , social c la s s , e t c . , to g e th e r w ith d a ta on th e com position of th e h o u se h o ld s among w hich th e p o p u la tio n is d is tr ib u te d . In m any c o u n tr ie s , in c lu d in g B rita in , th e c e n su s co llects a d d itio n a l, n o n -d e m o g ra p h ic info rm ation a p p e rta in in g to h o u se h o ld s, c o v e rin g s u c h m a tte rs a s hou seh o ld te n u r e a n d am en ities, n u m b e r of room s a n d ty p e of d w ellin g . T h e p u b ­ 35

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F PO P U L A T IO N

lish ed r e s u lts a re not confined to r e p o rtin g th e nu m b ers of people o r h o useholds w ith p a rtic u la r a ttr ib u te s , b u t a re p r e ­ sen ted in th e form of complex c ro s s-ta b u la tio n s of two or more c h a ra c te ris tic s , th e cells of which a re r e f e rr e d to as c en su s 'v a ria b le s '. A few, sm all-scale national c e n su se s w ere ta k e n before th e end of th e e ig h te e n th c e n tu ry (Iceland 1703, Sweden 1749, Norway 1769) b u t th e f ir s t d etailed c e n su s of a population of se v e ra l millions was th a t of th e U nited S ta te s in 1790. B ritain and France followed su it in 1801 a n d fir s t cen su se s w ere held in most E uropean c o u n trie s d u rin g th e n in e te e n th c e n tu r y , th e la te s t - an d b ig g e st - b ein g th a t of the R ussian Empire in 1897. N in eteen th c e n tu ry f irs t c e n su se s also o c c u rre d in 'E u ro p e O v e rse a s' (C a n ad a , New Zealand 1851; A u stralia 1881), in se v e ra l Latin American c o u n trie s and in India (1881), b u t most of th e 'T h ird World' was not covered u n til well in to th e tw e n tie th c e n tu r y , o ften not u n til a fte r World War II (G hana 1948, N igeria 1952, Zaire 1974). THE BRITISH CENSUS O rigin an d Development The U nited Kingdom h as one of th e w o rld 's lo n g est s e rie s of te n -y e a rly (d ecennial) c e n su se s - eig h te e n in all - of which th e f irs t was held in 1801 an d th e most re c e n t in 1981; only 1941, becau se of wartim e co n d itio n s, is m issing from th e s e rie s . An additional 10 p e r cen t sample c e n su s was held in 1966, b u t p ro p osals fo r 'm id -term ' sam ples in 1976 an d 1986 were re je c te d on g ro u n d s of economy. With th e p assag e o f tim e, th e B ritish ce n su s h as become in c re a sin g ly com plex, collecting and p u b lish in g a p ro g re ssiv e ly g re a te r volume and ra n g e of inform ation; major chan g es have also o c c u rre d in th e o rg a n isatio n of th e ce n su s o peration an d th e geog rap h ical b a se fo r th e collection and publication of th e d a ta . T he f ir s t fo u r c e n su se s (1801, 1811, 1821, 1831) r e ­ corded only th e n u m b ers of males and fem ales in each house and fam ily, w ith a simple occupational breakdow n in to five categ o ries: p e rso n s in a g r ic u ltu r e , tr a d e , m a n u fa ctu rin g , h a n d ic ra fts an d 'o th e r s '; d e ta ils w ere also collected on th e num bers of h o u se s, families p e r house and w h e th e r th e houses were v acan t o r o ccu p ied . A q u e stio n on age was ad ded in 1821. T he 1841 c e n su s re c o rd e d much th e same inform ation, b u t th e re w ere im p o rtan t o rg an isatio n al c h a n g e s. T he h o u se­ hold became th e basic u n it of enum eration and th e completion of th e c e n su s form (o r 's c h e d u le ') becam e th e re sp o n sib ility of th e head of th e h o u seh o ld , a s s is te d w here n e c e ssa ry by th e E num erator. T he local co n d u ct of th e c en su s in E ngland and Wales was tr a n s f e r r e d from th e P a rish O v e rse e r to th e 36

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

R e g istra r of B irth s , M arriages an d D e a th s, a p o st e sta b lish e d when v ital re g istra tio n becam e com pulsory in 1837. T his change did not o ccu r in S cotland u n til 1855 a n d th e 1841 and 1851 c e n s u s e s , like th e ir p r e d e c e s s o rs , w ere o rg a n ise d b y th e official schoolm aster o r 'o th e r fit p e rs o n ' in each p a ris h . By 1861, ho w ev er, th e whole of G reat B rita in had a uniform o rganisation com prising E num erato rs re sp o n sib le to local R e g is tra rs , who in tu r n re p o rte d to th e R e g istra rs-G e n e ra l o f Scotland and of E ngland and Wales. U nder th is sy ste m , th e basic te rrito ria l u n it became - an d rem ains to th is day - th e Enum eration D istric t (E D ), a small piece o f te r r ito r y capable of b ein g co v ered by one in d iv id u al. For th e c e n su se s of 1841 to 1901 (1861 to 1901 in Scotland) each E num erator re c o rd e d th e d e tails from th e cen su s sch ed u les in an 'e n u m e ra to r's b o o k ', from which th e d ata w ere e x tra c te d fo r tab u la tio n . From 1911 o n w ard s, punched c a rd s w ere u sed fo r th e re c o rd in g and s o rtin g of cen su s d ata an d th e e n u m e ra to rs' books h ave con tain ed only adm inistrative d etails an d a h ead co u n t o f th e population of th e ED; th e la tte r is u sed in th e p re p a ra tio n of th e population to tals p u b lish e d in th e Prelim inary R ep o rts (se e below ). The con fidentiality of th e b o o k s, as of th e sc h ed u le s th em selv es, is m aintained fo r 100 y e a rs : th o se fo r th e c e n su se s of 1841 1881 in clu siv e have now been re le a se d a n d form an invaluable reso u rce for detailed s tu d ie s of th e dem ographic and social s tru c tu r e of th e population in th a t p e rio d . The second h alf of th e n in e te e n th c e n tu ry also saw a m arked in c re a se in th e amount of inform ation collected and p u b lish ed . The 1851 c e n su s was much more detailed th a n its p re d e c e sso rs: q u e stio n s w ere a sk e d not only on s e x , age and occupation, b u t also on m arital s ta t u s , re latio n sh ip to th e head of h o usehold, b ir th p la c e , n a tio n a lity , e d u ca tio n , econ­ omic activ ity (w o rk in g , unem ployed, re tir e d ) an d w h e th e r th e ind iv id u al was d e a f, dumb o r b lin d . In 1891, ad d itio n al q u e s ­ tions w ere ask ed on th e in d iv id u a l's employment s ta tu s (em ployer, em ployee, self-em p lo y ed ), th e ability to sp eak Welsh (in Wales) o r Gaelic (in S cotland) an d on th e num ber of rooms in each h o u seh o ld 's accommodation. In 1911, th e in ­ d u s try in which th e in d iv id u al w orked was re c o rd e d , a s well as h is /h e r o ccu p atio n , and th e r e w ere q u e stio n s on th e fe rtility of m arried women. From 1841 to 1901 in c lu siv e , d a ta collected a t th e ED level w ere a g g re g a te d fo r publication b y R eg istra tio n S u b D istric ts , D istric ts and C o u n tie s, u n its which did not necessarily coincide w ith th e co n tem p o rary a d m in istrativ e divisions. T his so u rce of confusion was rem oved in 1911, when th e g eographical b a se was a lte re d to fit th e p a tte rn o f Local A u th o rity A reas. For th e c e n su se s of 1911 - 1971 in ­ clu siv e, EDs w ere su b d iv isio n s of W ards an d C ivil P a rish e s and ED d ata could be a g g re g a te d th e n c e to LAAs, which formed th e b a s is of ta b u la tio n s in th e p u b lish ed volum es. The 37

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

same applied in 1981 in E ngland an d Wales, b u t in Scotland EDs w ere b ased on postcode u n its . C h an g es in th e b o u n d a rie s of LAAs betw een su ccessiv e c e n su se s p re s e n t problem s in th e stu d y of in te rc e n sa l c h a n g e : in th e case of population c o u n ts, at le a s t, th e se can be overcome b y re fe re n c e to th e ta b le s p u b lish ed in th e c e n su s volum es which re c o rd , in g re a t d e ­ ta il, th e b o u n d a ry ch an g es w hich have o c c u rre d since th e p rev io u s c e n s u s , to g e th e r w ith th e n um bers of people a f­ fected . Special a rra n g e m e n ts had to be made following th e re o rg an isatio n of local g overnm ent in 1974/75. T hese involved th e publication of two s e ts of 1971 c e n su s volum es, one giving data fo r 1971 LAAs an d a second co n tain in g 1971 d a ta r e ­ ag g re g a te d to th e new LAAs e sta b lish e d in 1974/75. T he amount and n a tu re of th e d ata collected co n tin u ed to change th ro u g h su c c e ssiv e c e n s u s e s . In 1921, th e fe rtility questio n was rep laced by one on n um bers of d e p en d e n t c h ild ­ re n , an d a new q u estio n was in tro d u c e d on place o f w ork, p erm ittin g th e e a rlie st s tu d ie s of tra v e l-to -w o rk (com m uting). The 1931 c e n su s om itted th e q u e stio n s on f e r tility /d e p e n d ­ en c y , education an d place of w ork b u t ad ded th o se on u n ­ employment an d 'u su a l re s id e n c e '. T he tw e n ty -y e a r in te rc e n s a l p e rio d re s u ltin g from the absence of a 1941 c e n su s was a time of major dem ographic and social chan g e a n d , fo r th is re a s o n , much additional in fo r­ mation was so u g h t in th e 1951 c e n s u s , making it th e most detailed th u s f a r . In ad d itio n to th e q u e stio n s p re v io u sly ask ed on se x , a g e , m arital s ta tu s , relatio n sh ip to head of hou seh o ld , b irth p la c e , in d u s tr y , occupation a n d employment s ta tu s , th o se on f e r tility , ed u catio n an d place of work were re in tro d u c e d ; q u e stio n s on household am enities - th e p r e ­ sence , absence o r sh a rin g of a p ip e d w ater s u p p ly , b a th o r show er, k itch en sin k , cooking stove and WC - w ere b ro u g h t in fo r th e f ir s t time. The 1961 c e n su s re p e a te d v irtu a lly all th e q u e stio n s ask ed in 1951 an d ad d ed new ones on household te n u re (o w n er-o ccu p ied , re n te d from th e local a u th o rity , p riv a te ly r e n te d , e tc ) , on 'u su a l re s id e n ts a b se n t on ce n su s n ig h t' (p e rm ittin g th e calculation of de ju re as well a s de facto p o p u latio n s) and on 'a d d r e s s one y e a r ago' (p e rm ittin g detailed an aly sis o f in te rn a l m igration m ovem ents). Following a p erio d of heav y im m igration, th e 1971 c en su s paid p a rtic u la r a tte n tio n to th a t a s p e c t. A lthough th e q u estion on natio n ality was d ro p p e d , each in d iv id u al was re q u ire d to sta te h is /h e r p a re n ts ' c o u n try of b ir th as well as h is /h e r own and h is /h e r d ate of e n tr y in to th e UK if b o rn a b ro a d , q u e s ­ tions su b se q u e n tly a tta c k e d fo r th e ir alleged racial u n d e r ­ to n e s. Usual a d d re s s fiv e , a s well as o n e, y e a r ago was also dem anded and th e 1971 c e n su s was th e f irs t to a sk fo r th e in d iv id u a l's mode of tra v e l to work ( c a r , b u s , tra in e tc ) and w h eth er o r not each household had th e u se of a c a r o r c a rs . In 1981, th e ra n g e of q u e stio n s was co n siderably re d u c e d , p a rtic u la rly as re g a rd s th e c o n ten tio u s m atter of im m igration. 38

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

Both 'd a te of e n try in to th e UK' an d 'p a r e n ts ' b irth p la c e ' were d ro p p e d . T he in te rn a l m igration q u e stio n was again confined to 'u su a l a d d re s s one y e a r a g o ', all fe rtility q u e s ­ tions were dro p p ed an d th e household am enities re c o rd e d w ere red u ced to b a th o r show er and WC. On th e o th e r h a n d , sev eral of th e classificatio n s u sed w ere e x p a n d e d - th o se on marital s ta tu s and mode of tra v e l to w ork, fo r exam ple. In term s of c e n su s o u tp u t - th e num ber of v a ria b le s re c o rd e d and th e d etail of th e c ro s s -ta b u la tio n s p ro d u ce d - th e 1981 cen su s h a s p ro d u c e d more inform ation th a n any o f its p r e ­ d ec e sso rs. Collecting and P ro cessin g th e Data The legal b a s is . In B rita in , as in most c o u n trie s , th e c en su s is com pulsory and is b ack ed b y th e force o f law. From 1801 to 1911, each c e n su s re q u ire d a new Act of P arliam ent, b u t the 1921 an d all s u b se q u e n t c e n su se s have been held u n d e r the p ro v isio n s of th e C en su s A ct, 1920, th e most im portant of which are as follows(i)

(ii)

T he Act a u th o rise s th e ta k in g of a c e n su s of p o p u ­ lation u n d e r th e d irectio n of th e a p p ro p ria te M inister (in 1981 th e S e c re ta ry of S ta te fo r Social S e rv ic e s) at in te rv a ls of not le ss th a n five y e a r s . T h u s no new Act of Parliam ent is re q u ire d to co n d u ct a ce n su s once five y e a rs have e la p se d , an d th e o p eratio n is d ire c te d by an O rd e r in Council. T he O rd e r p re s c rib e s th e q u e stio n s to b e ask ed w hich, u n d e r th e term s of th e A ct, m ust be confined to th e following to p ics: (a ) nam e, s e x , ag e; (b ) occu p atio n , p ro fe ssio n , tra d e o r employm ent; (c ) n atio n a lity , ra c e , b irth p la c e , la n g u a g e ; (d ) place of ab o d e, c h a ra c te r of dw elling; (e ) condition as to m arria g e, relatio n to head of fam ily, is s u e b o rn in m arriag e; (f) 'a n y o th e r m atter w ith re s p e c t to which it is d e sira b le to obtain s ta tistic a l inform ation w ith a view to a sc e rta in in g th e social o r civil condition of th e p o p u la tio n '. T his la st p ro v isio n m ight a p p e a r to give th e c e n su s a u th o ritie s th e pow er to a sk any q u e stio n th e y w ish , b u t in p ra c ­ tice all p ro p o sals co n c e rn in g th e o rg an isa tio n o f th e c e n s u s , th e q u e stio n s to be ask e d an d th e p u blication of th e r e s u lts a re su b ject to th e s c ru tin y of P a rlia ­ m ent. The d ra ft C ensus O rd e r is d e b a te d in - an d is not uncommonly am ended b y - b o th H ouses of P arlia­ m ent, an d not u n til th e final v e rsio n is a p p ro v e d can th e M inister is s u e th e a p p ro p ria te C en su s R eg u latio n s.

P a rtic u la r a tte n tio n is paid to th e co n fid en tiality o f th e inform ation collected an d no d a ta may be re lea se d to any 39

B R I T I S H AND U N IT E D S T A T E S C E N SU S E S O F P O P U L A T IO N

ce n su s u s e r - which ap p lies to o th e r governm ent d ep artm e n ts as well as to local governm ent o fficials an d p riv a te o rg a n ­ isa tio n s an d in d iv id u a ls - in su ch a way th a t it would reveal the c h a ra c te ris tic s of an id en tifiab le p e rso n o r household. The complex 'c o n fid en tiality r e s tr a in ts ' d e sig n ed to meet th is req u irem en t have been d e sc rib e d in detail elsew here (D ew dney, 1981). The most im p o rtan t a re th a t (i) all p o p u ­ lation d a ta fo r a re a s w ith few er th a n 25 in h a b ita n ts a re 's u p ­ p re s s e d ' ( i .e . not p u b lis h e d ), w ith th e excep tio n o f to tal population n um bers of males and fem ales; (ii) all household d a ta fo r a re a s co n tain in g few er th a n e ig h t households a re s u p p r e s s e d , e x cep t fo r th e nu m b er of ho u seh o ld s. T hese ru le s affect le ss th a n one p e r cen t of ED 's b u t much la rg e r num bers of sm aller a re a s such as p o stco d e u n its o r g rid s q u a re s . F u rth e rm o re , th e a ctu al fig u re s p ro d u c ed are 'a d ju s te d ' by th e "th e addition o f a q u asi-ran d o m p a tte rn o f +1, -1 ,0 to th e in d iv id u al c e lls". Collecting th e D ata. C ollecting, p ro c e ssin g and p u b lish in g th e d a ta a re th e re sp o n sib ilitie s of th e c e n su s offices - in Scotland th e G eneral R e g iste r Office (G R O (S )), in N o rth ern Irelan d th e C ensus Office of th e D epartm ent of F inance, and in England and Wales th e Office of Population C en su se s and S u rv e y s (O PC S). T he last-n am ed also h as a g en eral re sp o n si­ b ility fo r e n s u rin g collaboration among th e th re e p a r ts o f th e UK (w hich, n e v e rth e le ss co n tin u e to collect and p u b lish th e ir d ata in slig h tly d iffe re n t w ays) an d w ith th e Isle of Man and C hannel Islan d s w hich, th o u g h tech n ically o u tsid e th e UK, hold c e n su se s a t th e same time. A la rg e , fo r th e most p a r t tem p o rary la b o u r force is re q u ire d to c a r r y out th e c e n s u s . In 1981 th is involved about 100 C ensus S u p e rv is o rs , o v e r 2000 C en su s O fficers (w ith 6500 A ssista n t C ensus O fficers) an d about 130,000 E n u m erato rs, to g e th e r w ith a la rg e tem p o rary clerical s ta ff in th e c en su s offices. A lthough th e d etails of o rg a n isa tio n w ere somewhat d iffe re n t in E ngland an d Wales, Scotland a n d N o rth e rn Irela n d re s p e c tiv e ly , th e post and d u tie s of th e E num erator were common to all p a r ts of th e U nited Kingdom an d it was th e E num erator who was resp o n sib le for th e g re a t b u lk of th e fieldw ork, c a rrie d out o v e r a p e rio d of fo u r o r five w eeks. As a lre a d y in d ic a te d , th e E num eration D istrict h a s long been th e b asic a re a l b u ild in g block in th e B ritish C e n su s. In 1981, G reat B ritain was d iv id ed in to 130,047 EDs; th u s , on av e ra g e , an ED co v ered an a rea of ab o ut 1.8 sq km and contained a population of some 400, d is trib u te d among 150 househ o ld s. In p ra c tic e , th e size of a ED an d th e num ber of people and h o useholds which it co n tain ed v a rie d g re a tly acco rd in g to local conditions of pop u latio n d istrib u tio n and d e n sity , with a predom inance of larg e EDs with small p o p u ­ lations in ru ra l a re a s an d small EDs w ith a b o v e-av erag e p o p u 40

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

lations in tow ns. EDs a re form ed, a n d th e ir b o u n d a rie s fix e d , on th e b a sis of two c rite ria : (i) th e y m ust fit w ithin th e b o u n d aries of W ards, C ivil P a rish e s an d LAAs (in Scotland th ey a re b ased on p o stcode u n its a n d sometimes re q u ire s u b ­ division to p ro d u ce Ward fig u r e s ) ; (ii) th e y m ust r e p re s e n t roughly equ al w ork -lo ad s fo r th e E n u m e ra to rs, who are paid a lump sum fo r th e ir e ff o r ts . T h u s an ED may com prise a ru r a l area of se v e ra l sq km w ith a s c a tte re d p o p ulation o r , in tow ns, a collections of s tr e e ts , a sin g le s tr e e t, p a rt o f a s tre e t o r ev en a sin g le block of fla ts . The E num erator is re sp o n sib le fo r th e following ta s k s : (ii) (ii) (iii) (iv ) (v )

th e id en tificatio n and lis tin g , p rio r to th e c e n s u s , o f all h o useholds in th e ED; th e d eliv ery to all id en tified h o u se h o ld s, two o r th re e w eeks b e fo re th e c e n s u s , of a p u b licity leaflet explain in g its n a tu re an d p u rp o s e ; th e d e liv e ry to each h o u seh o ld , w ithin a p e rio d of te n d a y s b efo re th e c e n s u s , o f th e c e n su s sc h ed u le; collecting th e sch ed u les an d ch eck in g them for e r r o r s an d in c o n siste n c ie s; w ith r e tu r n v is its to e r r a n t h o useholds w here n e c e s sa ry ; th e p rovision of a prelim inary count o f th e p o p u ­ lation of th e ED fo r u se in th e p re p a ra tio n o f th e p u b lish ed Prelim inary R e p o rt.

C learly , th e a c cu racy of th e c e n s u s d e p e n d s on th e care and co n scien tio u sn ess w ith which th e E num erator c a rrie s out th ese ta s k s and th e co n sisten cy w ith which h e /s h e a d h e re s to the in s tru c tio n s an d d efin itio n s laid down by th e ce n su s office. (OPCS 1981). Once collected an d c h e c k e d , th e com­ pleted sch ed u les a re p a sse d up th ro u g h th e chain of command to reach th e c e n su s offices re sp o n sib le fo r th e p ro d u ctio n of th e r e s u lts . P ro cessin g th e d a ta . Betw een th e re c e ip t of th e c e n su s in p u t - th e com pleted sch ed u les - an d th e em ergence o f th e ce n su s ou tp u t - th e p u b lish e d re s u lts - th e re o c c u rs a v a s t p ro c e s s ­ ing o p eratio n . In 1981, th e re s id e n t population of G reat B ritain totalled 53.6 million, of whom 98.5 p e r cen t liv ed in 19.5 million p riv a te h o u seh o ld s, each o f w hich p ro d u c ed a household sched u le (d iffe re n t sc h e d u le s w ere u sed fo r th e 0.8 million liv in g in 'communal e sta b lis h m e n ts '). T he sc h e d u les fo r England and Wales an d fo r Scotland (w hich d iffe r in detail) are rep ro d u c e d by R hind (1983) a n d th e q u e stio n s u se d in 1971 an d 1981 have b een d isc u sse d in detail b y Dewdney (1981, 1985) and o th e r s . T h is m aterial is not re p e a te d h e re : suffice it to say th a t th e modern B ritish c e n su s collects an enorm ous q u a n tity of raw d a ta . In 1981, in additio n to h is /h e r name (w hich rem ains wholly c o n fid e n tia l), e ig h t pieces o f inform ation w ere re q u ire d 41

B R I T I S H AND UNITED S T A T E S C E N S U S E S O F P O P U L A T IO N

from each in d iv id u al: se x , d ate of b ir t h , m arital s ta tu s , r e ­ lationship in ho u seh o ld , w h ereab o u ts on c e n su s n ig h t, u su al a d d re s s , u su al a d d re s s one y e a r ago an d c o u n try of b ir th ; all p e rso n s aged 16 o r o v e r w ere re q u ir e d , in a d d itio n , to s ta te th e ir 'd e g r e e s , p ro fessio n al and vocational q u alifications' (if any) and ’w h eth er w o rk in g , r e tir e d , h ousew ife, e tc la st week1; th o se at work had to p ro v id e th e name and b u s in e s s of th e ir em ployer, th e ir o ccu p atio n , th e ir employment s ta tu s and th e ir means of tra n s p o r t to w ork; th o se no lo n g e r w orking had to p ro v id e th e f ir s t th re e of th e s e item s in relation to th e ir most re c e n t jo b . In a d d itio n , six pieces of inform ation w ere re q u ire d from each h ousehold: num b er of room s, te n u re , sh a rin g o r lacking b a th a n d /o r WC, num ber of c a rs o r v an s available, and w h e th e r o r not th e h o u se h o ld 's accommodation was se lf-c o n ta in e d . T he E num erator had to p ro v id e a location re fe re n c e , d istin g u ish betw een hou seh o ld s in perm anent and tem porary (c a ra v a n s , e tc ) s tr u c tu r e s an d to s ta te w h e th e r o r not th e household s h a re d a b u ild in g w ith o th e r ( s ) (A dditional inform ation was re q u ire d in S c o tla n d ). T he n et re s u lt was a data set of approxim ately 1000 million p ieces of inform ation e n te re d on some 19.5 million sc h e d u le s. The much sm aller d ata s e ts from th e f irs t eleven c en su se s (1801-1901 in clu siv e) w ere a g g re g a te d and ta b u late d manually and from 1911 to 1961 th e d a ta w ere coded and p u n ch ed onto c a rd s fo r m echanical s o rtin g and a g g re g a tio n . In 1971 and 1981, ho w ev er, d a ta m anipulation was c a rrie d out by com puter an d th e new technology p e rm itted th e pro d u ctio n of more num ero u s, more detailed an d more complex ta b u latio n s th a n e v e r b e fo re . D ata p ro c e s s in g in th e se two c e n su se s in ­ volved th e coding of th e item s re c o rd ed on th e c en su s sch ed u les fo r th e p ro d u c tio n of com puter tap e files from which th e many c e n su s ta b u la tio n s w ere e v e n tu ally p ro d u c e d . Not all th e d ata w ere fully coded and s to re d : a co nsiderable num ber of item s w ere e x tra c te d from a 10% sample o f th e ce n su s sc h e d u le s. C oding an d sto ra g e involved two s e ts of o p eratio n s: allocation to areal u n its d ep en d ed on th e locational re fe re n c e s e n te re d on each sch ed u le b y th e E num erator; allocation of household an d p o pulation c h a ra c te ris tic s to th e a p p ro p ria te c a teg o ries re q u ire d coding of th e an sw ers to th e v ario u s q u e stio n s on th e sc h e d u le . T he coding of 1000 million item s was clearly a m assive ta s k . Much of th e c e n su s sch ed u le is now in th e form of tic k -b o x e s , to which code n u m b ers a re a tta c h e d , an d th is p a rt of th e o p eratio n is relativ ely sim ple. C ertain item s, how ever, re q u ire tran sfo rm atio n b efo re coding: d a te s o f b ir th (co n sid ered to p ro d u ce more a c c u ra te a n sw ers th a n do re q u e s ts fo r chronological a g e ) , fo r exam ple, h av e to be tra n sla te d in to age (in y e a rs ) at c e n su s d a te . O th e rs , like 'b u s in e s s of em ployer' an d 'o ccu p atio n ' have to be allocated to th e categ o ries of th e S ta n d a rd In d u s tria l and S ta n d a rd O ccupational C lassification re s p e c tiv e ly . D ata involving the 42

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

location of in d iv id u a ls re q u ire p a rtic u la rly lab o rio u s t r e a t ­ ment; th e a n sw ers to th e m igration q u e stio n - 'u s u a l a d d re s s one y e a r ago' - have to be allocated to th e a p p ro p ria te a re a and c ro s s -re fe re n c e d w ith 'u s u a l a d d re s s on c e n su s n ig h t' to pro d u ce th e n u m b ers of people who h av e moved betw een p a irs of a re a s . In c e rta in in s ta n c e s , item s a p p e a rin g in th e c e n su s o u tp u t a re d e riv e d , d u rin g c o m p u te r-p ro c essin g o f th e prim ary coded d a ta , from more th a n one item on th e sch e d u le . A prim e example is th e division o f th e population in to 'socio-econom ic g r o u p s ', w hich is a r r iv e d a t by c ro s s re fe re n c in g th e a n sw ers on economic a c tiv ity , in d u s tr y , occupation an d employment s ta tu s . Such d ifficu lt item s a re coded only on a 10% sample b a s is , a m ethod applied in 1981 to th e q u e stio n s on re la tio n sh ip in h o u seh o ld , o ccu p atio n , in ­ d u s tr y , w orkplace, means of tr a n s p o r t to work and educational q u alificatio n s. Given th e am ount of w ork in v o lv ed , th e publicatio n of th e final re s u lts by Septem ber 1984 was a major achievem ent. The Publication of th e C en su s R e s u lts . As a lrea d y in d ic a te d , the p u b lish e d re s u lts of th e B ritish c e n su s a re by no means confined to simple c o u n ts of th e n u m b ers of p e rso n s o r households in each of th e c a te g o rie s u se d in coding and a g g re g a tin g th e raw d a ta , b u t co n sist of s e ts of ta b le s c ro s s refe re n cin g two o r more p o p u latio n s o r household a ttr ib u te s . T aking two exam ples a t random th e re a re fig u re s fo r each areal u n it show ing th e num ber of econom ically-active m arried females aged 20-24 w orking full-tim e in th e week befo re th e ce n su s, an d th e num ber of p e rso n s in p riv a te households in ow ner-occupied accommodation w ith an econom ically-active o r re tire d head of household in socio-econom ic g ro u p 3 (se lfemployed p ro fessio n al w o rk e rs ). T hese 'c e n s u s v a ria b le s' normally a p p e a r as c o u n ts, from w hich 'd e riv e d v a ria b le s' su ch a s p ro p o rtio n s of all people o r households - may be calculated b y th e c e n su s u s e r . The p u b lish e d re s u lts of th e 1981 c e n su s a p p e a re d in a v a rie ty of form s, of which b y fa r th e most com prehensive were th e tra d itio n a l b o u n d volum es a n d th e Small A rea S ta tistic s (SA S). T he P ublish ed v olum es. A se t o f b o u n d volum es h a s b een p ro d u ced from e v e ry B ritish ce n su s: in 1981 th e y num bered more th a n 1200 an d co n tain ed some 18,000 p a g e s of ta b le s . D etails may be o b tain ed from th e c e n su s o ffices' c a ta lo g u es, from th e an n u al HMSO c atalo g u e, G overnm ent P ublications an d from th e lis ts p ro d u ced b y D ewdney (1981, 1985) an d o th e rs . T he volumes to g e th e r p re s e n t th e full ra n g e of c e n su s d ata ta b u la te d for Local A u th o rity A reas an d o th e r "official" te rrito ria l u n its . In sum m ary, th e y a re of th r e e main ty p e s : 43

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

P relim inary R e p o rts , C ounty Volumes an d N ational Volumes. (a) Prelim inary R ep o rts The B ritish c e n su s h as a long tra d itio n of p ro d u c in g , w ithin a s h o rt p e rio d a fte r c e n su s day an d well in ad v ance of th e main r e s u lts , a selection of p relim in ary d a ta . In 1981, in a su ccessfu l attem p t to sp eed th e p ro d u c tio n of th e defin itiv e volum es, th is p relim in ary m aterial was re d u c e d to a minimum. T h ree Prelim inary R e p o rts w ere p u b lis h e d , one each fo r England an d Wales, S cotland an d N o rth e rn Ire la n d , b a se d on Enum erators' co u n ts of th e population p re s e n t on c e n su s n ig h t. In a d d itio n , th e r e was a special P relim inary R eport on Towns: u rb a n an d ru r a l a re a s g iv in g p opulation to tals io r u rb a n a re a s as d efin ed by th e ir pre-1974 b o u n d a rie s. O th e r early p ro d u c ts w ere th e two s e ts of H istorical T a b le s, 1801-1981, com paring population c o u n ts in 1981 with th o se of all p re v io u s c e n su se s. (b ) T he C ounty R ep o rts (R egional R ep o rts in S cotland) T hese w ere th e la rg e s t single block of 1981 c e n su s m aterial 148 volumes in all. T h ese con tain a s ta n d a rd set o f ta b le s , g en erally a t th e level of Local A u th o rity A re a s, co v e rin g th e main dem ographic, econom ic, h o u sin g an d household v a ria b le s. In E ngland an d Wales, each re p o rt com prised two se p a ra te ly bound p a r ts , P a rt 1 co n tain in g th e 100% an d P a rt 2 th e 10% v a ria b le s. In S co tlan d , th e r e w ere fo u r volumes fo r each reg io n : Volumes 1 and 2 re p lic a te d most of th e ta b le s in th e English and co u n ty r e p o r ts , Volume 3 gave additional v a r i­ ables re c o rd e d only in S cotland an d Volume 4 p re s e n te d selec­ te d v a ria b le s for lower lev els of a g g re g a tio n su c h a s W ards, Civil P a rish e s and p o stc o d e s. T he New Towns re p o r ts - two volumes each for Scotland an d fo r E ngland and Wales - con­ tain ed th e s ta n d a rd c o u n ty re p o rt ta b le s fo r th o se u n its . In N o rth ern Irelan d only one e q u iv alen t volume was p ro d u c e d , th e R eport fo r B elfast Local G overnm ent D is tr ic t, th e re s t of th e d ata a p p e a rin g in th e 'n a tio n a l' volum es. (c) N ational Volumes T his se t in clu d ed some volum es co v erin g G reat B ritain - b u t n e v e r th e U nited Kingdom - a s a w hole, and o th e rs fo r Scotland, N o rth ern Ire la n d , E ngland an d Wales o r Wales o n ly , a situ atio n re fle c tin g th e c o n tin u in g com partm entalisation of th e B ritish c e n s u s , w hich is c a rrie d o u t b y a se p a ra te office in each " c o u n try " . T he national volum es fell in to two main cla s s e s , th o se which re p lic a te d , u su ally at d iffe re n t levels of ag g re g a tio n , th e ta b le s found in th e c o u n ty and regional re p o r ts , an d th o se which p re s e n te d additional m aterial. In th e firs t c a te g o ry w ere th e tw o -p a rt N ational R e p o rt, G reat 44

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

B rita in , th e S co ttish Sum m ary, th e R ep o rt fo r Wales an d th e N o rth ern Irelan d Summary R e p o rt. A second se t of national volum es, o fte n r e f e r r e d to as the 'c e n su s topic' volum es, p ro v id e d ad d itio n al inform ation on su b jects not in clu d ed o r only p a rtia lly co v ered in th e c o u n ty / regional re p o rts an d sum m ary volum es. Each con tain ed a valuable ap p en d ix in d ic a tin g in w hich o th e r volum es additional tab u latio n s re la tin g to i t s topic a re to b e fo u n d . S everal to p ics w ere d ealt w ith in volum es co v e rin g th e whole of G reat B ritain (N o rth e rn Ire la n d h a s its own s e t of topic volum es) - S ex , Age an d M arital S ta tu s , G reat B rita in , Usual R esidence, GB, P e rso n s of P ensionable A ge, G B, Com­ munal E stab lish m en ts, G B, an d Q ualified M anpower, GB. O th ers covered G reat B rita in b u t th e re was also a s e p a ra te S cottish volume - C o u n try of B ir th , Economic A ctiv ity , Work­ place an d T ra n s p o rt to Work. In th e ca se s of H ousing and Households and Household and Family C om position, th e r e were se p a ra te volum ei fo r Scotland a n d fo r E ngland an d Wales. Migration d ata occupied no few er th a n 24 volum es: National M igration, G reat B ritain P a rt 1 (100%) an d P a rt 2 (10%), equiv alen t Regional M igration re p o r ts fo r each of th e nine sta n d a rd reg io n s of E ngland an d Wales an d fo u r S co ttish Migration volum es, 1 an d 2 co n tain in g th e 100% an d 3 a n d 4 of the 10% d a ta . Finally th e r e w ere two special volum es on language - Welsh L anguage in Wales an d th e S co ttish Gaelic R e p o rt. (d ) 'K ey S ta tistic s' volumes The sh e e r scale of th e p u b lish e d o u tp u t p r e s e n ts problem s for the u s e r re q u irin g q u ick and easy acc e ss to a b asic piece of inform ation for a p a rtic u la r a re a . To su p p ly th is n e e d , OPCS and GRO(S) jointly p ro d u ced th e sum m ary volume Key S ta t­ istic s fo r Local A u th o ritie s, G reat B rita in , w hich p r e s e n te d , in 19 ta b le s , some 120 v a ria b le s fo r th e 459 local governm ent d is tr ic ts , most o f them in p e rc e n ta g e form . A f u r th e r six 'k ey s ta tis tic s ' volum es w ere p ro d u c e d fo r specially id en tifie d u rb a n a re a s - Key S ta tistic s fo r U rban A re a s, G reat B rita in , Key S ta tistic s for Localities (S co tlan d ) an d fo u r regional volum es, Key S ta tistic s fo r U rban A re a s, N o rth , M idlands, South E ast an d South West an d Wales. (e) O th er Publications An in novation of th e 1981 c e n su s was th e p rin tin g of selected variab les many of them in p e rc e n ta g e form , in booklet se rie s - C ounty M onitors, Ward an d Civil P a rish M onitors a n d P arlia­ m entary C o n stitu en cy M onitors) A dditional inform ation on economic a c tiv ity is available from a s e t o f Economic A ctivity B ooklets, p u b lish ed in m icrofiche. JnT addition to th e d a ta th em selv es, th e c e n su s offices have p ro d u ced a much g re a te r ra n g e o f e x p la n a to ry docum en­ 45

B R I T I S H AND U N IT E D S T A T E S C E N S U SE S O F P O P U L A T IO N

tatio n th a n on any p re v io u s o ccasion. Too e x te n siv e to be listed h e re , th is m aterial in c lu d e s C en su s Monitor s e rie s and some 200 U ser G uides, d e ta ils of which can be o b ta in ed from OPCS. The Small A rea S ta tistic s (S A S ). SAS have now rep la ced the tab les in th e p u b lish e d volum es as th e main re so u rc e fo r re s e a rc h on th e B ritish p o p u latio n . T h e ir developm ent b eg an in 1961 w hen, fo r th e f ir s t tim e, d a ta w ere made available fo r EDs in selected a re a s , an d co n tin u ed in 1966, when d a ta w ere pro v id ed fo r all EDs. The su p p ly of SAS was sy stem atised in 1971 b y th e ir p ro v isio n in a s ta n d a rd form at of 1571 v aria b les a rra n g e d in 28 ta b le s. In 1981 th e y co n sisted of some 4300 v ariab les (5000 in S cotland) a rra n g e d in 52 ta b le s , o rg a n ise d into 10 p a g e s. T he la y o u ts for 1971 and 1981 may be ob tain ed from OPCS an d have been re p ro d u c e d b y Rhind (1983) and Dewdney (1981, 1985). SAS a re available a s p rin te d copies (th e 'p a g e s' re fe rre d to a b o v e ), as m icrofiche, on microfilm o r on m agnetic ta p e for com puter m anipulation, which is now th e form most commonly u se d . Each v ariab le h a s its u n iq u e cell n u m b er. Data can be e x tra c te d an d m anipulated by re fe re n c e to th e se cell n u m b ers, which can be u se d to c o n stru c t 'd e riv e d v a ria b le s '. As an exam ple, cell 50 is 'to ta l r e s id e n ts ' an d cell 112 is 'm arried female re s id e n ts aged 30-34'. T h u s th e la tte r can be e x p re s s e d as a p e rc e n ta g e of th e form er by th e specification x 100. SAS a re available fo r E num eration D is tric ts , W ards, Civil P a ris h e s , Postcode s e c to rs (S cotland o n ly ). Local A uthority A reas an d P arliam en tary C o n stitu e n c es. Space does not perm it a d esc rip tio n of th e c o n te n ts of th e SAS ta b le s: suffice it to say th a t th e y would a p p e a r to contain v irtu a lly e v e ry m eaningful classificatio n and c ro ssta b u la tio n which it is possib le to p ro d u ce from th e raw d ata re c o rd e d on th e ce n su s sch ed u les. With th e a p p earan ce of SAS in a form su ita b le fo r man­ ipulation b y co m p u ter, much a tte n tio n h a s been d ev o ted to th e p re p a ra tio n of s ta tis tic a l p a c k a g e s fo r u se w ith th e se d a ta . The most sig n ifican t of th e s e is SASPAC, p ro d u c ed specifically fo r th e 1981 SAS b y th e U n iv ersities of Durham and E d in b u rg h u n d e r c o n tra c t to th e Local A u th o ritie s Management S erv ices an d C om puter Committee (LAMSAC). SASPAC can be ru n on a v a rie ty o f d iffe re n t co m p u ters, p ro d u c e s s tra ig h tfo rw a rd an a ly se s of th e d a ta an d p r e p a re s d ata fo r in p u t to more complex s ta tis tic a l and m apping p a c k ­ a g e s. Among th e l a tte r , one of th e most widely u se d is GIMMS, p ro d u ced b y Gimms L td . of E d in b u rg h . F u rth e r developm ent along th e se lin es seems likely b e fo re th e n e x t B ritish c e n s u s , sch ed u led fo r A pril 1991.

46

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T I O N

THE AMERICAN CENSUS O rigin a n d D evelopm ent T he most fu n d am en tal a sp e c t o f th e A m erican C e n su s is th a t its o rig in s a re b o u n d u p w ith th e fo rm ation of th e n atio n s ta te . I t is e n s h rin e d in th e C o n s titu tio n . T h e d e le g a te s to th e C o n stitu tio n a l C o n v en tio n o f 1787 d e c id e d th a t b o th s ta te ap p o rtio n m e n ts fo r th e H ouse of R e p re s e n ta tiv e s a n d d ire c t tax a tio n sh o u ld b e b a s e d u p o n p o p u la tio n d is tr ib u tio n . By com bining th e tw o, th e le g is la to rs so u g h t to a c h ie v e a b alan c e betw een p r e s s u r e s fo r o v e r - a n d u n d e r - e n u m e ra tio n . A rticle I, Section 2 of th e C o n stitu tio n d e c re e s th a t a C e n su s sh o u ld be h eld a t le a s t o n ce e v e ry 10 y e a r s com m encing w ith in th r e e y e a r s of th e f i r s t m eeting of C o n g re s s . E ven now , th e p rim a ry d r iv in g -fo rc e b e h in d th e C e n su s rem ain s a p p o rtio n ­ m en t, e v id e n c e d b y th e C o u rt a c tio n s ta k e n b y n o r th e a s te r n c itie s a g a in s t th e B u re a u of C e n s u s a f te r 1980 on th e b a s is of alleg ed u n d e r-e n u m e ra tio n ; o th e r u s e s o f C e n su s d a ta h a v e , of c o u rs e , b u rg e o n e d sin c e 1790. T h e f ir s t n atio n al C e n s u s a c tu a lly p o s t- d a te d some 38 e a rlie r C e n su se s c a r r ie d o u t in th e C olonies, th e e a rlie s t of w hich was h eld in V irg in ia in 1624, a n d most o f w hich w ere c a rrie d o u t at th e re q u e s t o f th e B ritis h B o a rd o f T r a d e . T h o u g h M adison a n d o th e r s in th e f ir s t C o n g re ss a rg u e d fo r a w ider in fo rm a tio n -c o lle ctin g ro le , th e 1790 C e n su s re c o rd e d only th e name o f th e h e a d of fam ily, a n d n u m b e rs th e r e in . T h ese w ere s u b - d iv id e d in to fre e w hite males (ab o v e a n d below 16 y e a r s o f a g e ) , fre e w hite fem ales, all o th e r fre e p e r s o n s , a n d s la v e s . No co u n t w as made of In d ia n s in th e h in te r la n d s , sin ce th e y d id n o t c o n tr ib u te to re v e n u e a n d , fo r a p p o rtio n m en t p u r p o s e s , fiv e sla v e s w ere to b e c o u n te d a s th e e q u iv a le n t of th r e e p e rs o n s ! T h e a c tu a l job of c a r r y in g out th is C e n su s w as mainly in th e h a n d s o f th e F e d e ra l M arshals in e ach o f th e th e n 16 S ta te s , who h ire d e n u m e ra t­ o r s . B e g in n in g on A u g u st 2 1790, th e C e n su s was com pleted in n in e m o n th s, th e la s t r e s u lts b e in g tu r n e d in b y M arch 1792. To c a r r y o u t th e C e n s u s , m uch local e n te r p r is e was re q u ire d - many e n u m e ra to rs h a d to p ro v id e th e ir own p a p e r . It is n o t s u r p r is in g th e r e f o r e th a t th e 3 .9 million in d iv id u a ls re c o rd e d w as g e n e ra lly a c c e p te d to be a sig n ific a n t u n d e rc o u n t o f th e tr u e p o p u la tio n . T h e C e n su se s h eld im m ediately th e r e a f te r in tro d u c e d a n u m b er of im p o rta n t in n o v a tio n s . T h e 1820 C e n s u s , fo r i n ­ s ta n c e , c o n ta in e d q u e s tio n s on w h e th e r em ploym ent w as in a g r ic u ltu r e , com merce o r m a n u fa c tu rin g (th o u g h th e r e s u lts w ere fo u n d to b e v e r y i n a c c u r a te ) . P rin te d s c h e d u le s a p p e a re d in 1830 a n d a c e n tra lis e d office fo r r u n n in g th e C en su s was c re a te d f o r th a t p u rp o s e in 1840 - th o u g h it was to b e d isb a n d e d o n ce th e r e p o r ts w ere is s u e d . By th a t tim e, th e b r e a d th of in fo rm atio n co llected had in c re a s e d 47

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F PO P U L A T IO N

dram atically, th e C e n su s Act of 1840 in s tr u c tin g th e office to collect "all su ch inform ation in relatio n to m ines, a g r ic u ltu re , commerce, m an u factu res an d schools as will e x h ib it a full view of th e p u r s u its , in d u s tr y , ed u catio n an d re so u rc e s of th e c o u n try " . From 1850 to 1870, th e M arshals w ere in s tru c te d not only to u se th e in d iv id u al r a th e r th a n th e household a s th e u n it of enum eration b u t also to p ro d u c e re p o r ts fo r civil divisions which th e y would c re a te an d w ere to b e known as co u n ties. By 1870, th e ra p id g row th in inform ation collected had reach ed a sto n ish in g p ro p o rtio n s . T h is h ad se v e ra l e ffe c ts , notably th a t th e M arshals w ere swamped w ith inform ation, were unable to v alid ate it p ro p e rly an d p ro d u c e d th e re p o rts only when th e d a ta w ere o b so lete. T he C e n su s Act of 1880 d id , in fa c t, in s titu te a tem p o rary C en su s office w ithin the D epartm ent of th e In te rio r an d made p ro v isio n fo r specially app o in ted en u m e ra to rs an d s u p e rv is o rs in place of th e M arshals. T he Act was also th e f ir s t to p ro h ib it e n u m e ra to rs from disclo sin g any inform ation collected in th e C e n su s. An innovation of g re a t moment in th e 1890 C ensus was th e in tro ­ duction of H ollerith's p u n c h e d c a rd ta b u la tin g m achines, b u t p e rh a p s ju s t as sig n ifican t was th e estab lish m en t o f a p e r ­ manent C en su s office in 1902. T h re e y e a rs la te r th is moved to th e D epartm ent of Commerce an d a C en sus g e o g ra p h e r was ap p o in ted . As well as b ein g th e f ir s t ta k en by th is new o rg a n isa tio n , th e 1910 C en su s also in c lu d e d a small experim ent w hich, w hilst soon ab a n d o n e d , h ad immense re p e rc u ssio n s for contem porary American C en su ses - th e u se of th e public mail serv ice to d e liv er q u e s tio n n a ire s . The 1940 C e n su s, ho w ev er, p ro v id e d th e p ro to ty p e for to d a y 's C en su ses: it in clu d ed th e f ir s t C en su s of h o u sin g and th e f ir s t s u b sta n tia l re c o rd in g of em ploym ent, unem ploym ent and m igration. P e rh a p s most im p o rta n t, h o w ev er, it in tr o ­ duced th e concept of sam pling to re d u c e th e am ount o f w ork in su b se q u e n t d a ta p ro c e s s in g . By 1960, only a few o f th e population item s were so u g h t from all of th e re sp o n d e n ts an d much of th e d istrib u tio n an d collection of C ensus form s was done b y mail. T h a t y e a r was also th e f irs t in w hich all C ensus ta b u la tio n s w ere made b y co m p u ter, th e C ensus B ureau h a v in g in sta lle d a UNI VAC 1 - a rg u a b ly th e firs t commercial com puter - in th e late 1940s. O th e r im portant tech n ical developm ents p io n eered o r a d v an ced by th e B ureau inclu d e FOSDIC o r Film O ptical S e n sin g Device fo r In p u t to C om puters. Special q u e stio n n a ire form s w ere d e sig n e d , filled in b y th e re s p o n d e n t, microfilmed an d th e n scan n ed b y com­ p u te r to obv iate k e y -p u n c h in g . As in B rita in (one y e a r l a t e r ) , th e 1970 C en su s saw a su b sta n tia l in c re a se in th e nu m b er of s ta tis tic s ta b u la te d and p a rtic u la rly in those fo r small g eo g rap h ic a re a s : d etails w ere released fo r 1.7 million city blo ck s an d 35,000 C en su s tr a c ts . Only a few b a sic population an d h o u sin g q u e stio n s w ere a sk e d 48

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

on a 100% sample b a s is , most b e in g co llected on a 15% o r 5% b a sis. T hat C en su s b u ilt heavily upon th e 1960 e x p erien c e of use of th e p ublic mail. S e p a ra te FO SD IC -readable q u e stio n ­ n a ire s w ere u se d fo r r u r a l an d fo r u rb a n a re a s an d 60% of th e to tal population in larg e m etropolitan a re a s receiv ed q u e stio n n a ire s b y mail a n d r e tu r n e d them a f te r com pletion by the same mechanism. E num erato rs c o n ta cte d only n o n ­ re sp o n d in g h o useholds o r th o se r e tu r n in g incom plete form s. Elsew here in th e c o u n try , form s w ere se n t b y mail and collected b y e n u m e ra to rs. THE 1980 CENSUS The C ensus C ontext The 1980 C en sus cost n early $1 b illio n , com pared with $222 million fo r th a t in 1970. T h is enorm ous e n te r p ris e was planned from 1973 onw ard s in th e c o n te x t of s e v e ra l im portant fa c to rs , including: -

-

-

a w idening ra n g e of u s e r n e e d s, esp ecially from commer­ cial ag encies fo r small a re a d ata ch an g es in life sty le w hich com plicate ta k in g th e C e n su s, e .g . th e su b s ta n tia l num b er o f illegal im m igrants, new form s of household h av e been c r e a te d , a n d liv in g in remote sp o ts h a d , if a n y th in g , become more common th e lab o u r m arket c h an g es (w o rk in g ho u sew iv es, e tc .) had re su lte d in few er sk illed an d c o n scien tio u s in d iv id ­ uals b ein g available as e n u m e ra to rs. It had also e n s u re d th a t fa r more calls would need to be made in th e e v e n ­ in g s to collect forms th e racial an d e th n ic v a ria tio n s in th e US e n s u re d th a t en u m erato rs in hom ogeneous a re a s h ad to be from th e same b a c k g ro u n d as th o se e n u m e ra te d , th e re b y compli­ catin g still f u r th e r th e choice o f e n u m e ra to rs.

The Mail Out-Mail Back C ensus Some 90% of th e US pop u latio n (b u t only th o se in 50% o f th e land a re a ) w ere en u m erated in 1980 u sin g a mail out-m ail b ack C ensus p ro c e d u re . T he claimed a d v a n ta g e s o f th is p ro c e d u re a re su b s ta n tia l: few er e n u m e ra to rs a re re q u ire d , hence sav in g c o s ts , th e household h a s time to re fle c t on a n sw e rs and pro v id e them more a c c u ra tely and it o ffe rs g r e a te r p riv a c y to th e re s p o n d e n t. In re a lity , h o w ev er, o th e r fa c to rs also led to its adop tio n . T hese in clu d ed th e d iffic u ltie s o f ob tain in g suitab le e n u m e ra to rs, th e rem o ten ess o f some se ttle m e n ts, a n d the relativ ely p oor q u a lity of th e US map b a s e , at le a st when com pared to th a t in B rita in . T he la st fa c to r is o fte n u n ­ ap p re c ia ted b y UK r e s id e n ts : th e la rg e s t scale o f com plete, co n siste n t map cov erag e in m ainland B rita in is 1/1 0 ,0 0 0 , with 49

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S OF P O P U L A T IO N

70% of th e a rea co v ered b y 1/1250 an d 1/2500 scale maps which a re con tin u o u sly re v is e d . H ence, p u rc h a s e of th e SUSI (S upply of U npublished S u rv e y Inform ation) in B ritain should p ro d u ce maps which a re no more th a n a few m onths o u t-o f d a te . By c o n tr a s t, th e la rg e s t scale co n tinuous co v erag e in the USA is a t 1/62,500 scale and many of th e se a re up to 40 y e a rs o u t-o f-d a te . In th e se c irc u m sta n c es, mailing lis ts o ften co n stitu te th e most u p -to -d a te detailed p o p ulation g eo g ra p h y . D espite th is , th e b e s t available maps of th e USA w ere com­ piled fo r each one of th e 300,000 Enum eration D istric ts fo r u se in th e field (below ). Mailing lis ts fo r 1980 w ere g en erally o b tain ed from commercial so u rc e s , th o u g h se v e ra l fo r th e same a re a w ere sometimes m erged an d th e r e s u lts ch eck ed by th e p o stal serv ice in mid-1979. P rio r to th e C e n su s, an en u m erato r system atically check ed all th e a d d re s s e s in an a re a , ad ding m issing ones to th e mailing lis t. T he n u m bers o f households in d iffe re n t a re a s from th e c ity block u p w ard s w ere th u s valid ated by com parison w ith local w a te r, gas and e le c tric ity and ad m in istrativ e re c o rd s : o v e r 32,000 of th e 39,500 local u n its of governm ent p a rtic ip a te d in th is ch eck in g p ro c e ss of th e a d d re s s lis ts . O th er ch eck s an d u p -d a te s co n tin u ed almost up to C en su s day on A pril 1 st. It is w orth s tre s s in g th a t, to make th e mailing operation a s u c c e ss, enorm ous p u b lic ity e ffo rts w ere made: C ensus m essages w ere placed in em ployees' pay p a c k e ts , on g ro cery b a g s, in th e media an d w ere ev en given out in schools. A resp o n se ra te of 74% was ach iev ed in th e mail out-m ail back operation (GAO 1982). The G eography of th e US C ensus The g eo g rap h y of C e n s u s -ta k in g . A ttach in g a g eo graphical refe re n ce to a C ensus re c o rd in th e 1980 C en su s re q u ire d th re e p ro d u c ts p ro d u c e d b y th e G eography Di-vision (Marx 1984). T hese w ere: (i)

(ii)

50

M aps, show ing named s tr e e ts and b o u n d a rie s of enum eration d is tr ic ts , C en su s t r a c ts , to w n sh ip s, c o u n tie s, cities an d major p h y sic a l fe a tu re s (su c h as railw ays) to aid position fix in g . T he maps w ere u se d in u rb a n a re a s prim arily b y en u m e ra to rs when check in g on n o n -re sp o n d e n ts . G eographic B ase Files (G B F )/D ual In d ep e n d en t Map Encoding (DIME) files. T h ese encode th e topological re la tio n sh ip s betw een s tr e e ts an d betw een th e postal a d d re s s and th e p o stal a d d re s s and th e block (see F ig u re 2 .1 ) . Given a GBF/DIME file, autom ated m atching of C en su s re c o rd s co n tain in g an in d iv id u al p o stal a d d re s s w ith a section of a s tre e t a n d hence

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

Adam« Twp

Z E B R A C IT Y 88 6 S 3 0 4 ______ |

303

11 o 1

m

(IS)

i -i a 3

i «» 11 l a o i 8 0 2

1

*2

•3

oos

!— ©

200

ED23

ED28

307

509

408

n

n

60 6

407

A i i l a u a * C o . , Ala .

(0 0 1 )

Straat Nam* MAIN ST. MAIN ST.

Fig. 2.1

From To P la c a Nod* Nod* 3 2

2 1

8855 -

Tract

15 15

Laft B lo ck

(0 1 )

R ig h t B lo ck

303

308

101-121

100-122

303

308

123-199

124-198

Portion of a US C en su s map show ing n o d es, s tr e e ts , b lo c k s, enum eration d is tr ic ts a n d postal n um bers ( to p ); and section o f p a r t o f th e eq u iv a l­ en t GBF/DIME file (from Marx 1984). with blo ck s is g en erally p o ssib le . M oreover, th e s tr u c tu r e of th e DIME file p e rm its autom atic ch eck in g th a t much of th e s tr e e t n etw o rk is com plete - o r a t le a st th a t w hat is re c o rd e d is c o n siste n t. T h is is vital since GBF/DIME files w ere c re a te d in colla­ b o ra tiv e p ro je c ts b etw een th e C en su s B u reau an d 300 local ag en cies. It is w orth n o tin g th a t th is only p ro v id e s implicit g eographical re fe re n c in g - th e s ta n d a rd GBF/DIME file co n tain s re la tio n sh ip s r a th e r th a n geom etry o f s tr e e ts , e tc . H ow ever, fo r th e 1% o f th e lan d a re a 51

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T I O N

(iii)

w hich in c lu d e s 60% o f th e p o p u la tio n , th e la titu d e a n d lo n g itu d e o f all th e s t r e e t n o d es h a v e b e en c o n v e rte d in to c o m p u te r form a n d p la n s a re in h a n d to e x te n d th is fo r th e 1990 C e n s u s (s e e b e lo w ). th e M aster R e fe re n c e F ile. F o r ea ch S ta te , th is c o n ta in s th e re la tio n sh ip b e tw e e n th e g e o g ra p h ic u n its ( s t r e e t s e c tio n s , e t c . ) in th e GBF/DIME file w ith th e a re a l u n its fo r w hich th e C e n su s r e s u lts a re to be ta b u la te d (h e n c e i t is th e US e q u iv a le n t of th e OPCS A rea M aster File w hich lin k s EDs to a v a r ie ty o f H ealth S e rv ic e a r e a s , e t c . ) . F or 1980, th is was c r e a te d b y a m assive c le ric a l e f f o r t to en co d e th e 2 .5 million b lock n u m b e rs on th e C e n su s m aps to g e th e r w ith th e en u m e ra tio n d is tr ic t n u m b e rs , C e n su s tr a c t n u m b e rs , p la c e nam es a n d c o d e s , e tc .

G iven th e s e th r e e e le m e n ts, th e c a p a b ility fo r autom atic ta b u la tio n o f r e s u lts fo r an alm ost in fin ite v a r ie ty of g eo­ g ra p h ic b a s e s e x is ts . T h e G eo g rap h y of C e n su s R e p o rtin g . T h e ta b u la tio n u n its fo r which 19o0 C e n s u s r e s u lts w ere p ro d u c e d w ere: Table 2.1:

Tabulation Units Recognised In the 1980 Census (from Marx 1984)

Political Areas

Statistical Areas

United States States & State Equivalents (57) States (50) D.C. (1) Outlying Areas (6) Countries, Parishes & Other County Equivalents (3,231) Minor Civil Divisions - MCD (30,491) Incorporated Places (19,176) American Indian Reservations (275) Indian Subreservation Areas (228) Alaska Native Villages (209) Congressional Districts - CD (435) Election Precincts (36,361) [In 23 participating States] School Districts (15,850) Neighbourhoods (s 27,750) ZIP Codes (a 37,000)

Regions (4) Divisions (9) Standard Consolidated Statistical Areas - SCSA (17) Standard Metropolitan Statistical Areas - SMSA (323) Urbanised Areas - UA (373) Census County Divisions - CCD (5,512) Unorganised Territories (274) Census Designated Places - CDP (3,733) Census Tracts (43,383) Block Numbering Areas - BNA (3,404) Enumeration Districts - ED (102,235) Block Groups - BG (156,163) (Tabulated parts - 200,043) Blocks (2,473,679) (Tabulated parts - 2,545,416)

Two o f th e s e ta b u la tio n u n its a re w o rth ex am ining in more d e ta il. T h e b lo ck is o fte n a v e r y sm all ta b u la tio n u n it in d e e d , a n d on ly se le c te d s ta tis tic s from th e 100% C e n su s sam ple a re p u b lish e d fo r i t . B lock d a ta a r e , h o w e v e r, p u b lish e d fo r all u rb a n is e d a r e a s a n d all in c o rp o ra te d p la c e s of 10,000 o r more p e o p le . In a d d itio n , o th e r a re a s can c o n tra c t fo r th e B u re a u 52

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O P U L A T IO N

to p ro d u ce block d a ta - th e to ta lity of th e S ta te s o f New Y ork, Rhode Isla n d , V irg in ia, G eorgia and M ississippi are available in th is form . T he C en su s tr a c t is an u n ch a n g in g a re a , hence facilitatin g com parison th ro u g h tim e. Unlike th e are a s of th e same name in tro d u c e d in 1981 B ritish C en su s re s u lts , th is is (in g e n e ra l) initially d e fin ed on th e g ro u n d by a Local C ensus S ta tistic a l A reas Committee as a homo­ geneous a rea of population an d h o u sin g ; o th e r governm ent and adm inistration is u rg e d to u se th e s e a re a s . T he concept and naming of th e 't r a c t ' is p rim arily d u e to Laidlaw whose assem bly of h isto ric a l an d c u r r e n t d a ta fo r small a re a s was th re a te n e d when New York ch an g ed th e b o u n d a rie s of th e ir assem bly d is tric ts (an d hence of C en su s re p o rtin g u n its ) in 1905. C en su s t r a c ts e x ist w ithin all th e S ta n d a rd M etropolitan S tatistical A reas an d some o th e r a re a s: th e ir a v era g e p o p u ­ lation is 4,000, w ith a ra n g e o f 2,500 to 8,000 people. The 1980 C en su s Q uestions The 1980 C en sus form s a re given in Kaplan and Van Valey (1980). Q uestions co v e rin g 7 population su b je c ts and 12 housin g su b je c ts w ere ask ed of e v e ry ho u sehold. T he p o p u ­ lation item s w ere nam e, relatio n sh ip to h o u seh o ld , a g e , 'r a c e ', se x , m arital s ta tu s an d S p an ish o rig in . T he rem aining q u e s ­ tions dealt with 26 population an d 20 o th e r h o u sin g item s b u t were collected on a sample b a sis as p re v io u sly d e sc rib e d : in to ta l, 79% of households got th e sh o rt (100% o n ly ) form s. A part from th e com plexity of th e race a n d e th n ic classification (Kaplan and van Valey 1980, p . 28 2 -3 ), p e rh a p s th e most in te re s tin g item s a re th o se collected on th e sample b a sis. Those in th e population section include e d u c a tio n , place o f b ir th , citizen sh ip and y e a r of im m igration, c u r r e n t lan g u ag e, a n c e stry , resid en ce an d a c tiv ity 5 y e a rs p re v io u sly , v e te ra n s ta tu s , d isa b ility , num ber of ch ild re n e v e r b o rn , m arital h is to ry , employment s ta tu s , place of w ork and jo u rn e y to w ork, th e in d u s tr y , occupation an d c la ss o f w o rk e r, num ber of weeks w orked in 1979 an d incom e. T he la s t of th e s e h as ap p eared in each C en su s since 1940 an d was specifically in ­ cluded b ecau se it is needed fo r F ed eral fu n d allocation form ulae. T he 100% sample hou sin g item s in clu d ed ac ce ss to the hou sin g u n it, plum bing (household am enities in th e B ritish C e n s u s ), num ber of room s, te n u r e , p ro p e rty v alu e fo r ow ner occupied u n its a n d , o th e rw ise , m onthly r e n t, and vacancy s ta tu s . T he sam ple-based q u e stio n s in clu d ed b u ild in g ty p e , num ber of s to rie s and p re se n c e o f an e le v a to r, so u rce of w ater an d sew age d isp o sa l, y e a r in which th e b u ild in g was c o n s tru c te d , th e y e a r in which th e p r e s e n t o ccupant moved in , h e a tin g eq u ip m en t, fu els u s e d , th e cost of u tilitie s and fuel, kitchen facilities, num ber of bedroom s a n d o f b athroom s, p re se n c e of telephone an d of a ir cond itio n ing a n d th e ow ner­ ship and u se of c a r s , v a n s and lig h t tr u c k s . C learly th is 53

B R I T I S H AND U NITED S T A T E S C E N S U S E S O F P O P U L A T IO N

ran g e of q u e stio n s is C en su s.

somewhat w ider th a n in th e

B ritish

C ensus R esu lts T he single re p o rt from th e fir s t US C en su s am ounted to only 56 p ag es: th e eq u iv alen t num ber of p rin te d pag es from th e fou r C en su ses from 1950 to 1980 w ere 50,000, 100,000, 200,000 and (ab o u t) 300,000. In a d d itio n , from 1960 o n w a rd s, in c re a sin g volumes of d a ta have b een made available in co m p u ter-read ab le form on m agnetic ta p e . The r e s u lts available d iffe r to some e x te n t, d e p en d in g on the transm ission medium a d o p te d . Hence th e p a p e r re p o rts beg an w ith Prelim inary Population an d H ousing Unit C o u n ts, su p e rse d e d by eq u iv alen t Final C ou n ts a n d , in a d d itio n , basic and some e x tr a co u n ts a re p ro v id e d in th e PHC s e r ie s , in ­ dividual re p o rts b e in g p ro d u c e d for block and C en su s tra c t level w ithin each SMSA an d a n o th e r fo r governm ental u n its in each S ta te . In a d d itio n , a whole se rie s of population and household re p o rts d e sc rib e th e b asic d a ta fo r a v a rie ty of areal u n its ; w hilst c ro s s -ta b u la tio n s do o c cu r in th e se r e p o r ts , th e y a re much less common th a n in th e ir B ritish c o u n te rp a rts . The same is tr u e (alth o u g h to a le s s e r e x te n t) fo r th e su b ject r e p o r ts , m ostly p ro d u c e d a t national level. C om puter ta p e s contain much more d etail b o th in term s of c ro ss-ta b u la tio n s an d g eo g rap h ical d etail - hence one tape (STF1C o r S ta n d a rd Tape File 1 fo r C ounties co n tain s well o v er one h u n d re d cells o r v a ria b le s fo r each of th e 3,000+ counties in th e USA. C en su s of Population and H ousing (1980) p ro v id es d etails of th e STF files which are readily o b tain a b le. It is w orth p o in tin g out t h a t, unlike th e B ritish policy of c h a rg in g by d ata p e r a re a l u n it, th e US B ureau of C en su s c h a rg e s only th e cost of copying th e d a ta . Hence a ta p e full o f d a ta from OPCS (say EDs in a co u n ty ) could cost £2,000 o r more, w hilst th e maximum c h a rg e fo r th e 'p u b lic dom ain' US d ata a p p e a rs to be ab o u t $100. One o th e r p ro d u c t p ro d u ced in th e US is w orth exam ­ inin g : th e Public Use M icrodata Sample tap e files which contain a small sample of u n id en tified in d iv id u al and household re c o rd s , each co n tain in g v irtu a lly all th e d etails o th e r th a n name an d a d d re s s fo r th o se people o r households selecte d : only S tates o r g ro u p s o f co u n ties a re id e n tifie d . N o rris (1983) pointed out th e a d v a n ta g e s of su ch d a ta in p e rm ittin g th e u s e r b o th to c re a te h is own c ro s s -ta b u la tio n s an d also to avoid th e ecological fallacy: he u rg e d th a t th e se d a ta should be made available for B ritain and d isc u ssio n s are now in han d betw een OPCS and th e Economic an d Social R esearch Council to see if an eq u iv alen t o f th e s e d ata can b e p ro d u c e d .

54

B R I T I S H AND U N IT E D S T A T E S C E N S U S E S O F P O PU L A T IO N

C onfidentiality Since 1910, it h as b een th e p ra c tic e th a t a P re sid en tial proclam ation is given of co n fid en tiality of C e n su s inform ation. The C a rte r proclam ation of 1979, fo r in s ta n c e , in clu d e d : " . . . . B y law , in d iv id u al inform ation collected will not be u sed fo r p u rp o s e s of ta x a tio n , in v e stig a tio n , o r re g u la tio n , o r in connection w ith m ilitary o r ju ry se rv ic e , th e com pulsion of school a tte n d a n c e , th e reg u latio n of im migration o r w ith th e enforcem ent of any natio n al, S tate o r local law o r O rd in an ce". Whilst th is is somewhat more detailed th a n a re th e term s of the 1920 C ensus Act in B rita in , th e in d iv id u al q u e stio n n a ire resp o n se s a re re ta in e d as co nfidential fo r a s h o rte r perio d (72 y e a rs com pared w ith 100 in B rita in ). In addition to th e to tal p ro h ib itio n of giv in g o f in d iv id ­ u a l's re c o rd s to o th e r a g e n c ie s, th e C en su s B ureau is ch arg ed with e n s u rin g th a t no in d iv id u a l's c h a ra c te ris tic s can be o btained from th e p u b lish e d r e s u lts . T he B ureau achieves th is in a d iffe re n t m anner to th e B ritish - few er c ro s s ­ tab u latio n s a re p ro d u ced an d th o se which a re a re o ften only pro d u ced fo r a re a s w ith more th a n a given population size ( e .g . th e Summary T ape File 5 is only available fo r S ta te s, SMSAs and SC SA s). Hence only simple c o u n ts a re given at the block level (a v e ra g in g about 70 p eo p le). Where d etailed d ata a re p re s e n te d , d ata su p p re ssio n te c h n iq u e s a re a p p lie d , b u t th e y d iffe r somewhat from the B ritish ap p ro ach . S u p p re ssio n in th e STF1 ta p e s can become q u ite complex: in g e n e ra l, fig u re s a re se t to zero if few er th an 15 people o r 5 h o useholds e x ist in a tab le o th e r th an those of b asic c o u n ts. B ut th ese th re s h o ld s can also be applied to num bers of S panish o rig in o r in d iv id u al racial group in selected ta b le s and com plem entary su p p re ssio n (su p p re ssio n on two o r more b a s e s , e . g . 'fiv e ow ners and five r e n te r s ') is u se d in some d a ta . A ccuracy US C en su ses have c h a ra c te ristic a lly u n d e rc o u n te d th e p o p u ­ lation th o u g h in g e n e ra l th e d iscrep an cy h as b een dim inishing in size from 3.3% in 1950 to 2.5% in 1970. H ow ever, th is u n d e rc o u n t v a rie s g re a tly betw een social an d eth n ic g ro u p s and in d iffe re n t a re a s of th e co u n try - in p a r tic u la r, th e e r r o r is g re a te r in re g a rd to H ispanics th a n fo r most o th e r g ro u p s. C learly all th is has major significance for apportionm ent at S tate level b u t th e n eed fo r ad justm ent to obviate th e u n d e rc o u n t is p re s e n t ev en down to th e 39,000 su b -S ta te u n its which gain from r e v e n u e -s h a rin g program m es b ased on population n u m b e rs. R efining th e ac cu racy can of co u rse be achieved b y v a rio u s su p p le m e n tary , p o s t-c e n s u s 55

B R I T I S H AND U NITED S T A T E S C E N S U S E S O F P O P U L A T IO N

c h e c k s, th o u g h th e se a re o ften e x p e n siv e . T he B u reau sp e n t $11 million in 1970 to re d u c e th e u n d e rc o u n t by 0.2%. In 1980, an estim ated $342 million was sp e n t in to ta l (GAO 1982) on re d u c in g th e u n d e rc o u n t. THE 1990 CENSUS US p lan n in g fo r a C en su s now b e g in s ab o u t 7 y e a rs p rio r to a C ensus an d much re a sse ssm e n t of th e 1980 C en su s was u n d e rta k e n in th e p erio d 1981-83. T he G eneral A ccounting Office of th e Com ptroller G eneral of th e US, fo r in sta n c e , c a rrie d o u t two in v e stig a tio n s (GAO 1982, 1983) on how th e 1990 C ensus could most efficien tly and economically be c a rrie d out b y m odifying 1980 p ro c e d u re s : th e D epartm ent of Commerce re sp o n se s to th e many d etailed recom m endations w ere also p rin te d in th e se r e p o r ts . B ounpane (1983) has w ritten a 'look ah ead ' from w ithin th e B u reau which d e sc rib e s the p ossible m odifications b e in g exam ined. One of th e most significant of th e s e h in g e s on th e in tro d u c tio n of th e TIGER (Topologically In te g ra te d G eographically E ncoding and R eferencing) S ystem , a com puter system to combine m aps, a d d re s s e s and C en su s g eo g rap h ical a re a s into one d a ta b ase. This h as two o b jectiv es - to re d u c e th e still high lev els of manual e ffo rt a t th e C en su s p re p a ra tio n ( c .f . th e highly autom ated C en sus tab u la tio n ) sta g e an d to re d u ce th e e r r o r s and in co n sisten cies th a t aro se in 1980 from h a v in g se p a ra te m aps, GBF/DIME files and M aster R eference Files. Broome (1984) h as given a d esc rip tio n of th e d esig n of th is system . To make th is function s a tis fa c to rily , a collaborative program m e with th e US Geological S u rv e y h as b een se t up to c re a te and con v ert in to com puter form a to tally new set o f 1/100,000 scale maps of th e USA b y 1987. THE BRITISH AND US CENSUS COMPARED Whilst th e y have many su p e rfic ia l sim ilarities - th e y a re larg e and complex o p e ra tio n s, o rie n ta te d to w ard s an a c c u ra te count o f th e p o p u latio n , held e v e ry te n y e a rs an d whose r e s u lts a re fundam ental for much p la n n in g an d re so u rc e allocation - th e re a re many d iffe re n c es betw een th e a p p ro a c h es u sed fo r C ensus ta k in g in th e two c o u n trie s. P e rh a p s th e most im portant of th e s e d iffe re n c es is th e method of d is trib u tin g and collecting th e q u e stio n n a ire s, th e way in w hich sam pling is c a rrie d o u t, th e ty p e an d ra n g e of q u e stio n s a sk e d , th e d ata en co d in g , v alid ation and tab u latio n p ro c e d u re s u s e d , th e n a tu re of th e b asic C ensus g eo g rap h y rec o rd e d an d th e cost of o b ta in in g th e re s u lts . N a tu ra lly , many of th e se a rise from d iffe re n c es in th e size of th e c o u n trie s, th e te r r a in to be c o v e re d , an d th e le g islativ e an d 56

B R IT IS H AND UNITED ST A T E S CENSUSES O F POPULATIO N

social context in which th e C ensuses are c a rrie d o u t. It may be th at the internationally exploited an d ra p id developm ents in new information technology and th e p re s s u re s upon C ensus agencies to reduce co sts ( e .g . GAO 1982) will lead to more commonality b u t each C ensus is essentially co ntex t-sp ecific. REFERENCES Bounpane, P .A . (1983) 'T he C ensus B ureau Looks to 1990' American D em ographics, O ctober, 1983, 1-8 Broome, F .R . (1984) 'T ig e r Prelim inary Design and S tru c tu re Overview ,' Paper P resen ted to Assoc. Amer. G eographers Annual Meeting in Washington D.C Census of Population and Housing (1980) Summary Tape File 1 Technical Docum entation, Data U ser S ervices Division, Bureau of C ensus, Washington D .C ., 2nd Edition 1982 (equivalent publications cover SFT 2 to 5) Denham, C. (1980) 'T he geography of th e c e n su s, 1971 and 1981', Population T re n d s , 19, 6-12 GAO, (1 9 8 2 F A $4 billion C ensus in 1990? Timely decisions on altern ativ es to 1980 p ro ced u res can save m illions, General Accounting Office, Washington D .C ., GGD-82-13 GAO, (1983) The C ensus Bureau needs to plan now for a more automated 1990 decennial c e n s u s , General Account­ ing Office, Washington D .C ., GGD-83-10 Kaplan, C .P . and Van Valey, T .L ., (1980) ( e d s .) , C ensus 80: Continuing th e F actfinder T ra d itio n , Bureau of C ensus, Washington D .C ., 490 pp Marx, R.W. (1984) Developing an In te g ra ted C artographic/ Geographic Data~ Base fo r th e US B ureau of C en su s, International B ureau of C ensus Memorandum Morgan, C ., and Denham, 'C ensus Small Area S tatistics (SAS): M easuring Change and Spatial V ariation', Popu­ lation T ren d s 28, 12-17 N orris, P. (1983) TvRcrodata From th e B ritish C e n su s', in D. W. Rhind ( e d s .) , A C ensus U sers H andbook, M ethuen, London, p p .301-19 OPCS, (1981) Census 1981: D efinitions, G reat B ritain , (CEN 81 DEF), HMSO, London Rhind, D.W. (1983) ( e d .) , A C ensus U sers' Handbook, London, Methuen UN, (1967) P rinciples an d Recommendations fo r th e 1970 Population C ensuses, UN Statistical P a p e rs, Series M, No. 44

57

C h a p te r T h ree FERTILITY PATTERNS IN THE MODERN WORLD J . Coward

Like most population c h a ra c te ris tic s , th e a n a ly sis o f fe rtility p a tte rn s can be in v e stig a te d at many d iffe re n t scales o f stu d y and th is c h a p te r th e re fo re exam ines fe rtility p a tte r n s with exam ples from a v a rie ty of p o in ts along th e scale continuum . At th e more macro lev el, fe rtility will be a sse sse d fo r th e co u n trie s and sub co n tin en tal a re a s of th e w o rld , em phasising the co n sid erab le d eg re e of contem porary v ariatio n an d the d iv e rsity of fa c to rs th a t influ en ce th e se d iffe re n tia ls. At a somewhat fin e r level of a n a ly s is , fe rtility v a ria tio n s in the B ritish Isles will also be exam ined. H ere, se v eral levels of ag g reg atio n a re c o n sid e re d , fo cu ssin g on th e c o n stitu e n t co u n tries of th e B ritish Is le s , regional and sub regional v a ri­ ations w ithin each of th e se a re a s and also fe rtility d iffe re n c es at th e d is tric t level in E ngland and Wales. P rio r to th e se specific exam ples, h ow ever, the c h a p te r d isc u sse s some g e n ­ eral issu e s co n cern in g th e geog rap h ical stu d y of fe rtility p a tte r n s , exam ining th e p o ssib ilities an d lim itations o f su ch stu d ie s, d ata availability an d th e n a tu re of th e o ry . GENERAL ISSUES A lthough th e field of population g eo g ra p h y has ex panded consid erab ly in re c e n t d ecad es, th e a n a ly sis of fe rtility p a t­ te r n s b y g e o g ra p h e rs rem ains a relativ ely n eglected a rea of stu d y . In many re s p e c ts th is is a s u r p r is in g fe a tu re because th e re a p p e a rs to be co n sid erab le scope a n d p o ssib ility fo r th e geographical stu d y of fe rtility . F irs tly , fo r exam ple, sp atia l variatio n s in fe rtility a re g en erally d isc e rn ib le fo r all the grad atio n s of th e scale continuum . S econdly, many c o u n trie s now have at le a st th e b asic d a ta so u rc e s n e c e ssa ry to in v e s ti­ gate sp atial v ariatio n s in fe rtility . T h ird ly , th e in te r - d is ­ cip lin ary n a tu re of fe rtility s tu d ie s , in which a wide ran g e of biological, dem ographic, socio-econom ic, so cio-psychological, political an d environm ental fa c to rs can be of p o te n tial ex p lan ato ry im portance, o ffe rs much o p p o rtu n ity to demon­ 08

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

s tr a te th a t th e geo g rap h ical ap p ro ach is one b a se d on the science (o r a r t) of s y n th e s is . F o u rth ly , while re al v a ria tio n s in fe rtility can be an im p o rtan t s tu d y in th em se lv es, th e y can also be u tilised as in d ic a to rs of w ider is s u e s , su ch as v a ri­ ations in social c h a n g e , o r re la te d to more ap plied population issu e s su c h as v a ria tio n s in o v erall pop u lation c h a n g e , d is tr i­ bution an d s tr u c tu r e an d also th e dem and fo r e d u c atio n , health an d serv ice p ro v isio n T his n eg lect of fe rtility s tu d ie s b y g e o g ra p h e rs was em phasised b y T re w a rth a (1953) o v e r th ir ty y e a rs ag o , b u t more re c e n t s u rv e y s of th e lite r a tu r e , su c h a s C larke (1977), Jones (1981, 1984), Schnell and Monmonier (1983), Rees (1981) an d Woods (1979, 1982) come to much th e same con­ clusion. Jones (1984), fo r exam ple, s ta te s th a t th e n eg lect is "serio u s an d in d e fe n sib le ", b u t has also s u g g e ste d th a t it can be ex plained b y fe rtility stu d ie s b ein g p e rc eiv e d a s le ss "geo­ graphical" (presu m ab ly re fle c tin g a ttr ib u te s of th e physical environm ent o r such sp atial a ttr ib u te s a s th e d ire c t e ffe c ts o f distan ce) th a n , fo r exam ple, s tu d ie s of m ortality o r m igration (Jones 1981). It is c e rta in ly th e case th a t in most circum ­ sta n c e s th e p h y sical environm ent p lay s little o r no p a r t in d irectly in flu en cin g fe rtility p a tte r n s , a lth o u g h , at b road scales of s tu d y , th e environm ent can e ffe c t p a tte r n s o f h ealth and diet which ca n , in tu r n , in flu en ce fe rtility c h a r a c te r­ istic s . On th e o th e r h a n d , th e role of d ista n c e can sometimes play a cru cial ro le , a s in , for exam ple, d ista n c e decay relatio n sh ip s o r in th e geog rap h ical diffu sion of c e rta in ideas and inform ation. O th er re a so n s, h ow ever, may also explain th e neglect o f fertility s tu d ie s . T hese could in c lu d e , fo r exam ple, th e lack of su b sta n tia l v a ria tio n in fe rtility in many developed co u n tries at th e b ro a d regional scale; th e g en erally g re a te r relativ e im portance of m igration in in flu en c in g population change a t regional and su b -re g io n a l scales an d p a rtic u la r problem s re la tin g to d ata availability a n d re lia b ility . In term s of d ata p roblem s, th e stu d y of fe rtility s h a re s many of th e p o ssib ilities an d lim itations of d ata av ailab ility common to any geographical stu d y of p o p u latio n . T h u s some o f th e lim itations include u n reliab ility in v ital re g is tra tio n an d c e n su s so u rce s due to u n d e r-r e p o r tin g , u n d e r-e n u m e ratio n o r m is-statem ent of inform ation (p a rtic u la rly am ongst sta tistic a lly u n d e r­ developed c o u n trie s ); u n av ailab ility of d a ta re g a rd in g c e rta in key ex p la n a to ry v a ria b le s a n d , u n til re c e n tly , little d ata available a t th e more detailed scales o f a n a ly sis. H ow ever, considerable p ro g re s s h a s b een made re c e n tly re g a rd in g data collection an d publication and th is h as g re a tly a d d ed to th e scope of geog rap h ical s tu d ie s of f e r tility . T h u s , a t an i n te r ­ national lev el, v a rio u s ag en cies a re c o n cern ed w ith estim ating and p u b lish in g p o pulation n u m b ers an d v ital ra te s (p a rtic u ­ larly th e U nited N ations an d th e Population R eference B u reau ) w h ilst, am ongst developed c o u n trie s in p a rtic u la r, g re a te r 59

F E RT IL IT Y P A TT E RN S IN THE MODERN WORLD

attention has been paid to p ro v id in g more detailed vital s ta t­ istic s, detailed census inform ation for small areas and record linkage via geographical inform ation system s. Furtherm ore, the in creasin g use of sample su rv e y s co n centrating on fe r­ tility o r including fertility questio n s can again prove u seful in the stu d y of spatial p a tte rn s of fertility - for example the recent work of th e World F ertility Survey an d , in many cou n tries, g re a te r reliance on household s u rv e y s. The ad v an ­ tage of such su rv e y s is th a t th e re se a rc h e r often has access to inform ation at th e individual level and th a t th e ran g e of information is much w ider th an th a t associated with th e sta n ­ dard cen su s. On the o th e r hand th ese su rv e y s are designed to be re p re se n ta tiv e of the whole co u n try and reliable in fo r­ mation at th e sub-national scale is probably only available at a broad regional level. The General Household S urvey in B ritain, for example, pro v id es much inform ation on p a tte rn s of family formation and family size at th e national level, although problems of sample size p ro h ib it spatial stu d ies at scales finer th an th a t of th e sta n d a rd region. T hus while it can be seen th a t population stu d ies will always be ham pered by "d ata p roblem s", th e ran g e and quality of th e data sources available for fertility stu d ies h ardly app ears of relevance in attem pting to u n d e rsta n d g eo g rap h ers neglect of th is subject. Finally, the role of th eo ry in spatial stu d ies of fertility can be b riefly a sse sse d . T here are two main so urces of theory th a t are applicable to geographical stu d ies of fertility involving, on the one h an d , a framework th a t is e ith e r e x ­ plicitly sp atial, such as diffusion th eo ry o r distance decay relatio n sh ip s, o r, on the o th er h an d , applying theories devel­ oped by o th er disciplines (often used in explaining changes over time) in a spatial se ttin g . T hese two ty p es are often combined in a single ap p ro ach , such as th e investigation of the effects of th e spatial diffusion of m odernisation upon resu ltin g spatial p a tte rn s . Of the firs t ty p e , diffusion theory provides a tem pting area of stu d y b u t one which pro v es diffi­ cult to in v estig ate. T hus it might be expected th a t ideas and information re g a rd in g fertility would sp read (at a v a riety of spatial scales) from certain core areas to outlying area s and th u s influence in v a ry in g d eg rees th e re su ltin g p a tte rn s of fertility . Jagielski (1980), for exam ple, examines how the spread of low fertility from u rb an are a s to su rro u n d in g ru ra l areas can reflect th e diffusion of th e small family norm. How­ ev e r, as Jones (1981) su g g e s ts , it is often difficult to e n v is­ age what actually co n stitu tes th e pro cess of diffusion. It is unlikely th a t knowledge of b irth control practices would diffuse in th is way because a v ariety of historical and a n th ro ­ pological stu d ies indicate th a t such knowledge is normally indigenously g e n erated . On the o th e r h an d , the sp re a d of information concerning the availability of certain artificial forms of b irth control might have more application to fertility 60

F E R T IL IT Y PA TT E R N S IN T HE MODERN WORLD

studies in certain co n tex ts, b u t even th e n th e key factor is generally the v ary in g motivations of individuals concerning the control of fertility ra th e r th a n knowledge about family limitation in itse lf. However .r a th e r th an th e sp rea d of in fo r­ mation reg a rd in g fertility lim itation, th e w ider process of the diffusion of cu ltu re may well have im portant rep ercu ssio n s on changing spatial p a tte rn s of fe rtility . T h u s Caldwell's (1977) example of th e influence and diffusion of w esternisation in Nigeria would seem to be p articu larly relev an t when examining the changing spatial p a tte rn s in th a t c o u n try . Diffusion of information concerning fe rtility behaviour rem ains a tem pting yet tan talisin g approach to the stu d y of spatial fe rtility . On the o th er h an d , th e im portance of distance decay relationships seems more clear c u t, p articu larly in a local context where there are variations in th e e x ten t to which individuals make use of certain services (su ch as family planning o r abortion) in relation to distance from th ese se rv ic e s. While certain compositional factors will of course influence the ta k e -u p of these facilities, th e influence of distance may also play a key role, as seen in a num ber of stu d ie s of family planning (Fuller 1984). Of th e th eo ries developed by o th e r disciplines and applied in a spatial co n te x t, th e most widely used eith er explicitly o r implicitly - has been th a t of modernisation theory and p articu larly in th e way in which demographic transition theory has been applied in a spatial sen se. In some ways th e seemingly clear cut n a tu re of m odernisation theory is appealing in th a t fe rtility decline is associated with the process of economic development and socio-economic change and these relationships can be applied to v ariations between and within co u n tries. In th e la tte r context the model of convergence-divergence provides an in te re stin g off-shoot of modernisation th eo ry (Coward 1985), although the p ro cess of modernisation does not always sp read with time o r necessarily reduce regional economic d ifferences in th e long term . The advantage of modernisation th eo ry is th a t it can be applied in a v ariety of se ttin g s and is sufficiently b road to incorporate many of the key variables affectin g fe rtility . On th e o th e r hand, the d isadvantages of such a framework - its ra th e r rigid evolutionary assum ptions, th e d iv erse n a tu re of the processes c h aracterisin g modernisation and th e ubiquituous collection of exceptions to th e norm - e n su re th a t modernisation theo ry cannot o ffer in its e lf an entirely satisfactory approach. T h u s, depending on th e scale of stu d y , o th e r theories may be of u se when considering spatial variations in fe rtility , involving, fo r exam ple, in te r generational wealth flows (Caldwell 1977, 1981, 1982), h is­ torical materialism (Woods 1982) and the new home economics (Schultz 1974). F urtherm ore, a more spatially explicit frame­ work has been adopted by Eversley (1982), linking th e spatial mobility of couples d u rin g th e ir c ritical period of family building with th e ir earn in g pow er, occupation and housing. 61

F E R T I L I T Y P A T T E R N S IN T H E MODERN WORLD

T his fram ew ork was a d o p te d to in v e s tig a te re g io n a l demo­ g ra p h ie s in B rita in , b u t it is lik e ly th a t su c h a fram ew ork can be ap p lied in o th e r s e ttin g s also . FERTILITY PATTERNS THROUGHOUT THE WORLD Two g e n e ra l fe a tu r e s c h a r a c te r is e c o n te m p o ra ry fe rtility p a t­ te r n s th ro u g h o u t th e w orld: th e c o n sid e ra b le d e g re e o f v a r i­ atio n an d wide ra n g e o f v a ria b le s th a t in flu e n c e su c h v a r i­ a tio n s. Each o f th e s e th em es a re exam ined in th is se c tio n . While th e c o n sid e ra b le d iffe re n c e s in fe rtility b etw een th o se c o u n trie s of th e N o rth e rn a n d S o u th e rn b lo cs (a s d e fin e d by th e B ra n d t R e p o rt) a re o f q u ite lo n g s ta n d in g , more re c e n t fe rtility d e c lin e s in some c o u n trie s o f th e S o uth also e n s u re th a t th e r e is now a c o n sid e ra b le r a n g e of v a ria tio n w ith in th is bloc. T h u s while fe r tility rem ain s h ig h in some re g io n s , most o f A frica fo r ex am p le, more m o d erate le v e ls h a v e now b een a tta in e d in much of S o u th E ast A sia, Mid A m erica a n d T ro p i­ cal S o u th A m erica (T ab le 3 .1 ) . H ow ever, o th e r a re a s h av e a tta in e d m uch low er fe r tility o v e r th e la st th r e e d e c a d e s , as seen in th e c a se s o f T em p e ra te S o u th A m erica, E ast A sia and th e C a rib b e a n (T ab le 3 .1 ) . M o reo v er, th e d iffe re n c e s b etw een in d iv id u a l c o u n trie s a re p a r tic u la r ly la rg e : in K en y a, for exam ple, c u r r e n tly d isp la y in g th e h ig h e s t lev el of f e r tility , a v e ra g e fe r tility is 8 c h ild re n p e r woman (on th e b a s is of c u r r e n t age sp ecific r a t e s ) , while in s u c h c o u n trie s a s C u b a , B a rb a d o s, S in g ap o re a n d Hong K ong th e T o tal F e rtility R ate is now 2 o r le s s . A v a r ie ty o f a p p ro a c h e s can b e u tilise d in a tte m p tin g to ex p lain th e s e v a r ia tio n s . In g e n e ra l te rm s it c e rta in ly a p p e a rs th a t th e re la tiv e ly low fe r tility of some c o u n trie s o f th e S o u th is a p ro d u c t o f v a rio u s fa c e ts o f m o d ern isatio n a n d socio­ economic d ev elo p m en t, a s s o c ia te d w ith c h a n g in g p o p u latio n com position a n d a ttitu d e s to family fo rm ation c o n s is te n t w ith low f e r tility . In d e e d , i t is te m p tin g to re ly on th e m odern­ isatio n fram ew ork b a s e d on th e d em o g rap h ic h is to ry of th e c u r r e n t W estern ised d e v e lo p e d c o u n trie s a n d assum e th a t c o n tin u e d m o d ern isatio n will in t u r n lead to low le v e ls of fe r tility in th e c o u n trie s o f th e S o u th . While it may a p p e a r u n re a lis tic to e x p e c t a re p lic a tio n o f d em o g rap h ic c o n d itio n s am ongst s u c h a r a n g e o f c o u n trie s d iffe rin g in te rm s of geo­ g ra p h ic a n d p o p u latio n s iz e , p o litical o r ie n ta tio n , social s t r u c ­ tu r e a n d d em o g rap h ic h is to r y it h a s b e e n a rg u e d th a t many p a ra lle ls can be fo u n d (v a n De Walle a n d K nodel, 1980). H ow ever, u s in g s u c h a fram ew ork a s m o d ern isatio n d o es ra ise q u e s tio n s c o n c e rn in g w h e th e r g e n e ra l p a tte r n s can be d is ­ c e rn e d a c ro s s th e p r e s e n t d e v e lo p in g c o u n trie s a n d , if so, th e sp ecific v a ria b le s in v o lv e d . A n aly sis of World F e rtility S u rv e y d a ta on d iffe re n tia l f e r tility in d ic a te s th a t c e rta in k ey fa c to rs can b e id e n tifie d (L ig h tb o u rn e e t al. 1982). From a s tu d y o f 29 d e v e lo p in g c o u n trie s it was fo u n d th a t fe rtility 62

T ab le 3 . 1 :

F e r t i l i t y R a te s by R egion f o r t h e E a r l y 1 9 8 0 's

R egion

T o tal F e rtility R ate

124 161 150 60 36 110 1036 393 1243 102 31 220 44

41 49 47 45 36 37 37 33 20 34 26 32 24

5 .9 6 .8 6 .6 6 .2 5 .2 5 .5 5 .3 4 .5 2 .6 4 .9 3 .4 4 .3 2 .7

1240 660 330 420 2490 4110 260 720 1360 1970

262 236 253 274 24

15 12 15 20 21

1 .8 1.7 2 .0 2 .5 2 .5

13000 11500 52 70 1 5940 8700

Per c a p it a GNP (US $)

-

IN THE MODERN

2120 2440

WORLD

^ S o u th e rn Europe o n l y . S o u rc e : 1984 World P o p u l a t i o n D ata S h e e t ( P o p u l a t i o n R e f e r e n c e B u re a u ).

10% higher than expected Tower Hamlets Watford Woking Crawley

Middlesborough Leicester

Newham Birmingham Hackney Knowsley Derby Gt. Grimsby Preston

Bolton Burnley Rossendale Ipswich S. Pembroke Oldham Rochdale Newport

Bradford Blackburn Pendle

MODERN

Luton Slough Mid-Devon East Hants Alnwick Wrexham Anglesea Radnor

IN THE WORLD

Mid. Bedford Halton Peterborough Copeland Maldon Eastleigh Gosport Rushmoor Redditch Rochester Hyndburn Richmondshire Tamworth Mid-Suffolk Kennet Dinefwr Presell Merthyr Tid. Rhymney Milton Keynes Suble Gillingham Rhondda

FERTILITY

oo

B.

Fertility > 10% lower than expected

Bromley Camden Hammersmith and Fulham Kensington and Chelsea Richmond Wandsworth Westminster Bath Cambridge Exeter Brighton Eastbourne Hove York Three Rivers Canterbury Oxford Ceredigion

Sheffield Solihull Kingswood Broxtowe Gedling Newcastle U.L Oswestry

S. Lakeland Epping Forest Winchester Harrogate

See Footnote 1 for explanation of terms.

-3

Bournemouth Cheltenham Blackpool S. Shrops

S. Bucks Brentwood Welwyn Hatfield Epsom Relgate Runnymede Spelthorne

FERTILITY

W. Derby W. Dorset Durham Cotsvold Beverley Oadby Castle Morpeth Selby Stratford U.A.

PATTERNS IN THE MODERN WORLD

F E RT IL IT Y PA TT E R N S IN THE MODERN WORLD

V ariations in m arital fe rtility also play an im portant role in ch a ra c terisin g are a s of relativ ely high and low fertility . Thus in four cases it plays a dominant role in influencing high fertility (Table 3 .5 ) and in th re e of th e se cases the areas concerned are towns c h a ra c terise d by the development of housing schemes o v er th e last fifteen y e ars (W atford, Woking and C raw ley). T his featu re seems co n sisten t with E versley's (1982) th e sis th a t many young couples in ten d in g family building move to are a s with reasonably good access to cheaper housing in o rd e r to use th e ir financial reso u rces most efficiently at a time when such re so u rces are often s tre tc h e d . This featu re also seems applicable to th e cases of Luton and Slough, where relatively high m arital fe rtility and p ro portions married co n trib u te to high fe rtility . In o th e r areas th e high marital fertility may be a re su lt of th e relatively large p ro ­ portions of th e population of New Commonwealth and Pakistan o rig in , as seen , fo r exam ple, in Tower Hamlets a n d , combined with high ex tra-m arital fe rtility , Newham and Hackney (In n e r London) and also Birmingham. On th e o th e r h an d , p a rtic u ­ larly low marital fe rtility b rin g s about low fertility in a v ariety of d ifferen t are a s (Table 3 .5 ). In some c a se s, for example, th e relatively high social s ta tu s of th e a reas con­ cerned may lead to lower fertility as in Solihull and Kingswood an d , combining with one of th e o th e r com ponents, West D erb y sh ire, Beverley and South S h ro p sh ire. The contribution of ex tra-m arital fertility in influencing age stan d ard ised fertility is often in conjunction with one of the o th er components. Here it is more d ifficult to a sse ss the spatial p a tte rn s because variatio n s in ex tra-m arital fe rtility by socio economic g rouping are not fully documented although it is known th a t ra te s are generally high amongst immigrant groups of C aribbean o rig in . More re c e n tly , th e link between high ex tra-m arital fertility and high youth unemployment has been su g g ested (Campbell 1984). On th is b a sis, some areas with relatively high fe rtility influenced wholly o r p a rtly by high ex tra-m arital fe rtility can be linked with relatively large C aribbean immigrant populations (H ackney, Birmingham and Newham) o r high levels of male and female youth unemploy­ ment (M iddlesborough, Knowsley and South P em brokeshire). Many of th e areas with low fertility in which low ex tra-m arital fertility plays a co n trib u to ry role ten d to be associated with relatively high social s ta tu s and low levels of y outh unemploy­ m ent, as seen in th e cases of W inchester, H arrogate and South B uckingham shire. It can also be noted th a t th e spatial variations around London seem to follow a d istin c t p a tte rn in th a t while In n er London is associated with are a s of b o th relatively high and low fe rtility , many of th e are a s of th e su b u rb an frin g e of G reater London are associated with low fe rtility (p articu larly on th e n o rth e rn , w estern and south w estern ed g es) while, on the o th e r h an d , many of th e outlying a reas are associated 80

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

with high fe rtility (su c h as L uton, Milton K eynes, Gillingham, R o ch ester an d R ushm oor). T hese la tte r fe a tu re s can again p e rh a p s be ex p lain ed in relatio n to E v e rsle y 's (1982) th e s is th a t couples in th e e a rly p h ase of family form ation (th o se with high level of c u r r e n t fe rtility ) may be in clin ed to move to more o u tly in g a re a s in se a rc h of c h e a p e r h o u sin g , while couples who have d elay ed o r fin ish ed family form ation may have g re a te r d isposable re s o u rc e s fo r th e g en erally h ig h e r house p ric e s in th e o u te r s u b u r b s o f G re a te r L ondon. It is difficult to v e rify th is h y p o th e sis from th e evid en ce p re s e n te d h e re , b u t th e re g u la rity o f th e sp atial p a tte r n s in a n d aro u n d London would s u g g e s t th a t c e rta in key socio-econom ic fa c to rs are o p e ra tin g . Finally, th e overall v a ria tio n s in age sta n d a rd is e d f e r ­ tility for th e to tal num ber o f d is tr ic ts (403) in E ngland and Wales can be a sse sse d in relatio n to a ra n g e o f sta n d a rd dem ographic an d socio-econom ic v a ria b le s d e riv e d from th e c e n su s. Some o f th e se fa c to rs p ro v e d ifficu lt to m easure as in , for exam ple, th e e ffe c ts o f th e m igration o f you n g couples w h ere, due to u navailability of more p re c ise in fo rm atio n , th e ra te of n e t m igration o v e r th e p e rio d 1971-81 fo r th e whole population is u tilise d . T he v a ria b le s co n c ern ed an d th e ir relatio n sh ip with fe rtility a re shown in T able 3 .6 . The zero o rd e r co rrelatio n s a re all in th e e x p e c te d d ire c tio n , w ith fo u r of th e e ig h t g re a te r th a n 0 .3 5 . Five o f th e v a ria b le s make a significant c o n trib u tio n to th e overall v a ria tio n s in fe rtility in the con tex t of a stepw ise re g re ssio n model, acco u n tin g fo r 50 p e r cen t of th e v ariatio n (T able 3 .6 ) . A p art from m arital s ta tu s , th e most im portant socio-economic v a ria b le s a re those of female unem ploym ent, im m igrant p o p u la tio n s, female e d u ­ cation an d th e p a rtic ip a tio n of m arried women in th e la b o u r force. H ow ever, th e la tte r two v a ria b le s only c o n trib u te mar­ ginal in c re a se s in th e p ro p o rtio n o f th e v aria tio n e x p lain e d . T hus it can be seen th a t on an o v erall b a s is c e rta in sta n d a rd dem ographic an d socio-economic v a ria b le s account fo r about one h alf of th e v a ria tio n in age sta n d a rd ise d fe rtility in England and Wales, in d ic a tin g th a t th e se a rc h fo r f u r th e r relev an t v a ria b le s should c o n tin u e . F u tu re a n a ly sis, fo r exam ple, will hopefully u tilise a more a p p ro p ria te m easure o f migration th a n th e one u tilise d h e re a s well a s exam ining housing c h a ra c te ris tic s in more d e ta il. FERTILITY VARIATIONS IN SCOTLAND The p io n eerin g c o n trib u tio n s to th e s tu d y o f re c e n t v a ria tio n s in S cottish fe rtility have b een th o se o f Jo n e s (1975) and Wilson (1978) who have exam ined v a ria tio n s in th e b ir th ra te in 1971-72 an d v a ria tio n s in family size m easured in 1971 resp e c tiv e ly . Both conclude th a t th e r e a re q u ite m arked d if­ feren ces in fe rtility a t th e county level o f a g g re g a tio n a n d 61

T a b le 3 . 6 : R e l a t i o n s h i p b e tw ee n a ge s t a n d a r d i s e d f e r t i l i t y and v a r i o u s d e m o g ra p h ic and s o c i o - e c o n o m ic v a r i a b l e s , 1981

P r o p o r t i o n s m a r r i e d (+) Female Unemployment (+) Im m ig rant P o p u l a t i o n * (+) Female E d u c a ti o n ( - ) P a r t i c i p a t i o n o f m a r r i e d women ( - ) S o c i a l c l a s s e s (+) T e n u re : owner o c c u p a t i o n ( - ) M i g r a t i o n (+)

0 .54 0 .3 7 0 .0 1 -0 .4 6 -0 .1 3 0 .3 9 -0 .0 6 0 .1 0

29 40 48 49 50 -

-

* L o g arith m ic tr a n s f o r m a tio n . VI X f e m a l e s 15-29 m a r r i e d ; V2 p r o p o r t i o n o f f e m a l e s aged 16-59 unemployed; V3 % o f p o p u l a t i o n b o r n i n t h e New Commonwealth, P a k i s t a n and I r e l a n d ; V4 % o f f e m a l e s w i t h h i g h e r e d u c a t i o n ; V5 % o f m a r r i e d women ag ed 16-59 e c o n o m i c a l l y a c t i v e ; V6 % o f p o p u l a t i o n w i t h h e a d s o f h o u s e h o l d i n s o c i a l c l a s s e s IV and V; V7 % o f p r i v a t e h o u s e h o l d s owner o c c u p i e d ; V8 o v e r a l l n e t m i g r a t i o n r a t e 19 71 -81 .

WORLD

R eg ressio n E q u a tio n :Y - 5 7 .4 + 0 .0 1 VI + 0 .1 1 V2 + 9 . 0 V3 - 0 .0 4 V4 -- 0 .0 2 V5

IN THE MODERN

VI V2 V3 V4 V5 V6 V7 V8

Z C o n trib u tio n to Z ero o r d e r v a r i a t i o n ( c u m u la t iv e c o rre la tio n % from s t e p w i s e reg ressio n) w ith f e r t i l i t y

PATTERNS

V ariab le (and h y p o t h e s i s e d r e l a t i o n s h i p w ith f e r t i l i t y )

FERTILITY

00

to

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

th a t c e rta in key v a ria b le s play an im p o rtan t role in c o n tri­ b u tin g to th e se v a ria tio n s . T h is sectio n exam ines fe rtility p a tte rn s in 1981 an d a tte m p ts to d isc e rn i f th e c h a ra c te ris tic s o b serv ed in 1971 a re applicable to more re c e n t v a ria tio n s. T he stu d y c o n c e n tra te s on c u r r e n t fe rtility b e ca u se q u e stio n s rela tin g to ch ild re n e v e r b o rn w ere om itted from th e U nited Kingdom c e n su s of 1981. Jo n es' (1975) s tu d y em phasises th a t v a ria tio n s in age and m arital s tr u c tu r e play a major role in in flu e n cin g sp a tia l v ariatio n s in th e b ir th ra te in 1971-72. On th is b a s is , th e r e ­ fore, it might be e x p e c te d th a t th e e x te n t o f v a ria tio n in those fe rtility m easures ta k in g account o f su ch v a ria b le s would be much le ss th a n th a t of th e b ir th r a te . H ow ever, th is does not a p p e a r to be th e case an d fo r 1981 th e m agnitude of relativ e v ariatio n in th e b ir th ra te (co efficient of v a riatio n = 11%) is only slig h tly g re a te r th a n th a t fo r th e index o f overall fertility (10%), which in d ire c tly s ta n d a rd is e s fo r a g e , and th e index of m arital fe rtility (9%), acco u n tin g fo r age and m arital s tr u c tu r e . In te re s tin g ly th e e x te n t o f re la tiv e v ariatio n in th e illegitim acy ra te (30%) is p a rtic u la rly la rg e . T he re lativ e degree of v ariatio n in th e b ir th ra te in 1981 was somewhat h ig h e r th a n th a t fo r 1971, alth o u g h th e c u r r e n t s tu d y is based on a la rg e r num ber of sp atial u n its as a re s u lt o f bou n d ary ch an g es (56 a s opposed to 31 u se d b y Jo n es) and consequently p ro v id e s a more detailed summary th a n th a t available fo r 1971. In 1981 th e g e n e ra l p a tte r n of v a ria tio n in th e b ir th ra te was bro ad ly sim ilar to th a t of 1971 (allow ing fo r d iffe re n c e s in th e spatial u n its u tilis e d ) , w ith re la tiv e ly low ra te s am ongst the b o rd e r a re a s , th e T ay sid e reg io n an d th e cities o f A berd een , D undee and E d in b u rg h . T h is c o n tra s ts w ith th e generally h ig h e r r a te s in much o f u rb a n c e n tra l S cotland, p artic u la rly th e e a s te rn side of th e Glasgow c o n u rb a tio n . One d ifferen ce, h ow ever, is th a t in 1981 re la tiv e ly h ig h b irth ra te s o c c u r in many of th e c o u n ties o f th e H ighlands and Isla n d s, w hereas th is fe a tu re was much le ss a p p a re n t in 1971-72. V ariations in age s ta n d a rd is e d fe rtility can b e b e st illu s tra te d b y u sin g C oale's in d ic e s, in which v a ria tio n s in overall fe rtility re fle c t th e v a rie d c o n trib u tio n s o f m arital fe rtility , p ro p o rtio n s m arried an d e x tra -m a rita l f e r tility .2 Indeed, v a ria tio n s in th e s e com ponents illu s tr a te th a t th e spatial p a tte r n s a re b y no means sim ilar (F ig u re 3 .3 ) . For exam ple, th e p a tte rn of v a ria tio n in m arital fe rtility is q u ite d iffe re n t from th a t of v a ria tio n s in e ith e r p ro p o rtio n s m arried 2Coales in d ices a re age s ta n d a rd is e d m easures b ased on a comparison betw een a c tu a l an d e x p e c te d b ir th s , w here th e la tte r a re d e riv e d from th e H u tte rite age specific fe rtility ra te s 1921-30 which a re tak en to re p r e s e n t n a tu ra l f e rtility . See Coale (1967). 83

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

o r e x tra -m a rita l fe rtility ( r = -0 .1 1 an d 0.15 r e s p e c tiv e ly ), with th e sp atial p a tte r n of m arital fe rtility dom inated b y th e relativ ely h ig h ra te s of many of th e w est coast h ighland a re a s , th e W estern Is le s , Moray an d some e a s te rn a re a s o f th e Glasgow co n u rb atio n (F ig u re 3 .3 ) . In d eed th is p a tte r n is bro ad ly sim ilar to th a t of v a ria tio n s in family size as exam ined by Wilson (1978), em phasisin g th e c o n tin u ity in m arital f e r ­ tility o v e r time an d a c ro ss b o th c ro ss-se c tio n a l a n d cohort m easu res. Both Jo n es a n d Wilson show th a t c e rta in key compositional v a ria b le s su c h as female a c tiv ity , social cla ss and religion play a sig n ifican t p a r t in ac c o u n tin g fo r v a ri­ ations in fe rtility an d it would th u s be e x p ec ted th a t v a r i­ atio n s in m arital fe rtility in 1981 would also be p a rtly explained b y su c h v a ria b le s . T he s tr e n g th of th e se asso ci­ atio n s a re sum m arised in T able 3.7 an d th e v a ria b le s co n ce rn ­ ing th e p ro p o rtio n of th e la b o u r force in a g ric u ltu re and hou sin g te n u re have also b een ad d ed to th e a n a ly sis In th e case of th e la tte r , it h as been shown re c e n tly th a t te n u re can play a major role in c o n trib u tin g to d iffe re n tia l fe rtility in B ritain (M urphy an d S u lliv an , 1983). T he co rrelatio n s betw een m arital fe rtility an d th e rem aining v a ria b le s a re all, with th e ex cep tio n o f te n u r e , in th e h y p o th e sise d d irectio n and th e v ariab le w ith th e g re a te s t e x p lan a to ry pow er is , sim ilar to Wilson's s tu d y , th a t o f th e p a rtic ip a tio n o f m arried females in th e paid la b o u r force (T able 3 .7 ) . In a stepw ise re g re ssio n model, two o f th e s e com positional v a ria b le s are sig n ifican t (p a rtic ip a tio n of m arried women in th e p aid lab o u r force an d religious d en o m in atio n ), a c co u n tin g for 60 p e r cent o f th e v a ria tio n in m arital fe rtility in 1981. On th e o th e r h an d , th e se com positional v a ria b le s p lay a much le ss im portant role in acco u n tin g fo r v a ria tio n s in p ro p o rtio n s m a rried , w here th e sp atial p a tte r n s a re le ss clearly d isc e rn ib le . In th is case low n u p tia lity o c c u rs in th e major c itie s (p e rh a p s due to th e in -m ig ratio n of you n g sin g le females to th e se a re a s as well as a g re a te r d e g re e of c o h a b ita tio n ), th e w e ste rn isle s an d p a r ts of th e H ighland an d Gram pian re g io n s. In te re s tin g ly , th e p a tte r n of illegitim acy is also v a rie d , re fle c tin g th e high ra te s in th e u rb a n a re a s of Glasgow an d D undee an d some are a s in th e H ighlands su c h a s Ross an d C rom arty an d also S u th erlan d (F ig u re 3 .3 ) . B road p a tte r n s of illegitim acy in S cotland have changed consid erab ly o v e r th e la st fifty y e a rs from one w h ere, d u rin g th e p re -w a r p e rio d , many r u r a l a re a s te n d e d to h av e re la ­ tively h ig h levels to one w h ere, sin ce th e mid 1950's, large u rb a n a re a s have g en erally had th e h ig h e st levels (Illsley an d Gill, 1968). T he c u r r e n t d is trib u tio n , th e r e fo re , seem s to refle c t elem ents of b o th th e old a n d th e new p a tte r n s . The in d ex of o v erall fe rtility is in flu en ced b y each o f th e th re e co n stitu e n t com ponents of f e r tility , b u t in th is ease it a p p e a rs th a t sp atial v a ria tio n s in m arital fe rtility play th e dom inant role in in flu en cin g o v erall fe rtility . F or exam ple, th e d e g ree 84

F E R T I L I T Y P A T T E R N S IN T H E MODERN WORLD

F ig. 3.3

V ariatio n s in 1981.

Coale’s in d ic e s o f f e r tility ,

S co tlan d

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

of association betw een th e s e two in d ices ( r = 0.84) is much h ig h e r th a n th e d e g re e of association betw een overall fe rtility and each of th e o th e r two com ponents. T h u s overall fe rtility is h ig h e r in th e w estern coast c o u n tie s, th e W estern Isles and th e n o rth ern m o st coast co u n ties w ith low er ra te s g enerally o c c u rrin g th ro u g h o u t th e r e s t of th e c o u n try (F ig u re 3 .3 ) . Of th e p re v io u sly m entioned socio-economic fa c to rs , only th a t of th e p a rtic ip a tio n o f m arried women in th e lab o u r fo rce is highly associated with overall fe r tility , in th is case accounting for 59 p e r cen t of th e v a ria tio n . To conclude, while it is d ifficu lt to compare th e spatial p a tte r n s in 1981 with th o se of 1971 d u e to ch an g in g b o u n d a r­ ies and v a ry in g d ata av ailab ility , th e re a p p e a r to be ce rta in co n sisten t fe a tu re s co n cern in g re c e n t S co ttish fe rtility p a t­ te r n s . T h u s c u rre n t v a ria tio n s a re still q u ite m arked and are by no means a p ro d u c t of v a ry in g age an d m arital s tr u c tu r e alone. Indeed c e rta in com positional v a ria b le s play a key role in in flu en cin g th e sp atial p a tte r n s and while th e e x ac t n a tu re of th e causal re la tio n sh ip s cannot be p re c isely specified from th e available a g g re g a te d a ta , it a p p e a rs th a t v a ria tio n s in overall and m arital fe rtility at th is scale of stu d y can be p a rtly a ttrib u te d to d iffe re n c es in female ac tiv ity p a tte r n s , while v ariatio n s in relig io u s denom ination e x e rt an im portant influence on v a ry in g m arital fe rtility . DIFFERENTIALS IN THE IRISH REPUBLIC T here a re sev eral ways in which fe rtility p a tte r n s in th e Republic of Irelan d a re of in te r e s t. F irs tly , fo r exam ple, th e overall level of fe rtility is p a rtic u la rly h ig h by West European sta n d a rd s an d th is fe a tu re can be a ttr ib u te d to a v a rie ty of economic, social, c u ltu ra l an d dem ographic fa c to rs (Cow ard 1978, 1980; K ennedy 1973). S econdly, fe rtility is in a s ta te of rap id ch a n g e , inv o lv in g a tr e n d to w ard s e a rlie r a n d more u n iv e rsa l m arriage coupled w ith g re a te r co n tro l of fe rtility within m arriag e. The pace o f th e s e ch an g es has been p a rtic u ­ larly m arked since 1971, in d ic a tin g th a t th e population o f th e Irish Republic is ra p id ly moving away from th e M althusian form of population lim itation (d elay ed m arriage and rela tiv ely high celibacy coupled w ith little re s tric tio n of fe rtility w ithin m arriage) tow ards more neo-M althusian form s c h a ra c te ris tic of most E uropean n eig h b o u rs (C ow ard 1982). H ow ever, while fe rtility h as generally declined o v e r th e last fifte en y e a rs (th e b irth ra te d ro p p in g from 22 p e r th o u san d to 19 p e r th o u san d betw een 1971 an d 1983), it still rem ains relativ ely high in a West E uropean c o n te x t. T h ird ly , sp atial v a ria tio n s in fe rtility a re q u ite m ark ed , ev en at fairly coarse levels of ag g re g a tio n , te n d in g to re fle c t, in p a r tic u la r, d iffe re n c es in economic developm ent and occupation s tr u c tu r e (Cow ard 1978, 1980). T his section b rie fly c o n sid e rs some of th e salient 86

V ariab le (expected r e l a t i o n s h i p w ith m a r i t a l f e r t i l i t y in p a re n th e s e s )

-J

1.0 0

0 .2 3 1 .0 0

V3 -0 .3 4 0 .1 9 1 .0 0

V4 -0 .6 9 0.0 7 0 .5 0 1 .0 0

V5

V6

0 .1 4 -0 .4 1 0 .2 0 -0 .0 9 1 .0 0

(+)

m a r r i a g e s c e l e b r a t e d i n t h e Roman C a t h o l i c m a r r i e d women w hose h u s b a n d f s s o c i a l c l a s s m a r r i e d women a g e d 1 6 -4 4 i n p a i d e m p lo y m en t. p r i v a t e h o u s e h o l d s ow ner o c c u p i e d . m ales in a g r i c u l t u r e .

0.07 -0 .6 0 -0 .5 0 -0 .3 8 0.31 1 .0 0

C h u rc h . is sk ille d

WORLD

00

V2

MODERN

P ro p o rtio n of P ro p o rtio n of non-m anual ( I l l n ) . V4: P ro p o rtio n of V5: P ro p o rtio n of V6: P ro p o rtio n of

VI

IN THE

V2: V3:

M a rita l f e r t i l i t y R e l i g i o n (+) S o cial c la s s (-) F em ale p a r t i c i p a t i o n ( - ) O w n er-o ccu p atio n (- ) Labour fo r c e in a g r i c u l t u r e

Z e ro O r d e r C o r r e l a t i o n s

PATTERNS

VI V2 V3 V4 V5 V6

and h y p o t h e s i s e d

FERTILITY

T ab le 3 .7 : R e l a t i o n s h i p s b e tw e e n m a r i t a l f e r t i l i t y e x p l a n a t o r y v a r i a b l e s , S c o t l a n d 1981

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

c h a ra c te ris tic s of re c e n t sp atial v a ria tio n s in fe rtility a t th e cou n ty scale of ag g re g a tio n an d th e n a tu re of th e ch an g in g sp atial p a tte r n s o v e r th e in te r-c e n s a l decade 1971-1981. As fo r many c o u n trie s , v a ria tio n s in th e Iris h b ir th ra te are s tro n g ly in flu en ced b y age an d m arital s tr u c tu r e . T his is o b se rv e d , fo r exam ple, w hen c o n tra stin g th e rela tiv e ly low ra te (16-20 p e r th o u sa n d ) in th e more economically d e p re sse d n o rth -w e s te rn p a r ts of th e c o u n try (tra d itio n a lly asso ciated with eld erly age s tr u c tu r e s an d low n u p tia lity ) w ith th e gen­ erally h ig h e r r a te s (23-27 p e r th o u sa n d ) of th e e a s te rn counties aro u n d D ublin. In d e e d , th e s e two v a ria b le s (m easured b y th e p ro p o rtio n s of th e pop ulation aged 20-34 and females m arried a t ag es 15-49) acco u n t for 71 p e r cen t o f th e v ariatio n in 1981. T he p a rtic u la rly high ra te s of th e e a s te rn counties aro u n d D ublin - in e x c e ss o f 23 p e r th o u ­ sand - e n s u re th a t n a tu ra l in c re a se is p a rtic u la rly high in th e se a re a s a n d , coupled w ith high ra te s of in -m ig ratio n , place con sid erab le p r e s s u r e on th e availab ility of la n d , h o u s­ in g an d re s o u rc e s in th e se a re a s . H ow ever, while age s tr u c ­ tu re h as a major influ en ce on th e b ir th r a te , it can be seen th a t con sid erab le v a ria tio n s in fe rtility a re still p re s e n t a f te r controlling fo r th is v a ria b le - a s in d ic a ted by th e overall deg ree of v ariatio n (v = 12%) in th e T otal F e rtility Rate com­ p a re d w ith th e b ir th ra te (v = 11%). C hanging p a tte r n s of age s ta n d a rd is e d fe rtility o v e r th e decade 1971-81 can b e b e s t illu s tra te d b y u tilisin g C oale's ind ices in which th e se p a ra te c o n trib u tio n s to overall fe rtility b y m arital fe rtility an d p ro p o rtio n s m arried (illegitim acy ra te s are gen erally low o u tsid e D ublin) can be a s s e s s e d . In d e ed , th e p a rtic u la rly m arked c h an g es in fe rtility which have o c c u rre d d u rin g th e decade 1971-81 h av e involved c o n tra s tin g tre n d s in each of th e main com ponents of fe rtility . T h u s , on a national b a s is , p ro p o rtio n s m arried in c re a se d by 8 p e r cen t while m arital fe rtility declined b y 25 p e r cen t and th e p a r ­ ticu larly la rg e decline in th e la tte r was re sp o n sib le fo r th e general decline of 18 p e r cen t in th e o verall level of age sta n d a rd ise d fe rtility (F ig u re 3 .4 ) . G enerally sp eak in g th e se chan g es took place th ro u g h o u t th e co u n ties and co u n ty b o ro u g h s of th e Iris h R epublic su ch th a t th e population in all of th e se a re a s u n d erw en t d eclines in o v e ra ll fe rtility and m arital fe rtility , while th e population of all b u t th re e a re a s (th o se u rb a n p opulations of D ublin, C ork an d Dun Laoghaire p a rtic u la rly affe c ted b y co n tin u ed in -m ig ratio n o f y o u n g single people) u n d erw en t in c re a s e s in p ro p o rtio n s m arried (F ig u re 3 .4 ) . In te re s tin g ly , th e g re a te s t re la tiv e in c re a se s in p ro p o rtio n s m arried o c c u rre d in th o se w e stern co u n ties which have gen erally d isp lay ed low er th a n a v e ra g e n u p tia lity an d th e re fo re it a p p e a rs th a t th e b ro a d reg io n al p a tte r n s of n u p tia lity a re co n v e rg in g . T he decline in m arital fe rtility is of p a rtic u la r in te r e s t fo r two re a s o n s. F ir s t, th e g en eral decline of 25 p e r cent is a p a rtic u la rly larg e re d u c tio n o v e r th e 88

V. CHANGE IN FERTILITY INOICES

1971-01

FERTILITY

V. Chon*«

C D -. E3>"

n

IN THE MODERN

DECLINE M MARITAL FORTUITY

PATTERNS

111 1»■«

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

decade an d is su re ly a p ro d u c t of th e v a rio u s social, econ­ omic, c u ltu ra l and dem ographic c h a n g e s th a t o c c u rre d d u rin g th e 1970's. Of th e se th e most im portant re g a rd in g fe rtility are th e con tin u ed declin es in a g r ic u ltu r e , th e g row th of an u rb a n based middle c la s s , r e tu r n m igration from B rita in , in c re a sin g employment o p p o rtu n itie s fo r m arried women, th e gro w th o f th e family p la n n in g m ovem ent, in c re a s in g s tre n g th o f feminism and risin g secu larisatio n am ongst th e y o u n g e r sectio n s o f th e population in p a rtic u la r. T he second point of in te r e s t is th a t the declines in m arital fe rtility have been q u ite la rg e th ro u g h o u t th e whole c o u n try an d w ere b y no means confined to th e p rin cip le u rb a n a re a s (F ig u re 3 .4 ) . T his s u g g e s ts th a t th e scale of social chan g e was also widely sp re a d and in th is con tex t th e movement of r e tu r n m ig ran ts to many of th e more ru ra l p a r ts of Ire la n d coupled w ith g overnm ent policy aimed at fo ste rin g economic developm ent and in d u s tria l grow th th ro u g h o u t th e whole c o u n try seem p a rtic u la rly a p p ro p ria te in attem pting to u n d e rs ta n d th e c h a n g in g a ttitu d e s to family form ation an d fe rtility . T he d eclines in o v erall fe rtility have been p a rtic u la rly m arked in th e main u rb a n a re a s (d u e to larg e re d u c tio n s in m arital fe rtility coupled with small o r no in c re a se s in p ro p o rtio n s m a rrie d ), while th e re d u c tio n s am ongst th e p o pulations of th e e a s te rn co u n ties have g e n e r­ ally been g re a te r th a n th o se of th e w estern co u n tie s. However th e fact th a t overall fe rtility h a s d eclined th ro u g h o u t th e whole co u n try (a t th is scale of s tu d y ) rem ains th e dom inant c h a ra c te ris tic of ch a n g in g fe rtility p a tte r n s o v e r th e most rec e n t in te r-c e n s a l decade. FAMILY SIZE IN NORTHERN IRELAND Similar to th e Iris h R ep u b lic, m arked sp a tia l v a ria tio n s in fe rtility a re ev id en t in N o rth ern Ire la n d . Compton (1978a, 1978b), for exam ple, h as exam ined th e d etailed p a tte r n s aro u n d 1971 and shows th a t th e d is trib u tio n of th e population by relig io u s denom ination, along w ith socio-econom ic and dem ographic fa c to rs , play im portant ro les in a cco u n tin g for th e se v a ria tio n s. While q u e stio n s re la tin g to family size w ere om itted from th e 1981 c e n s u s, a fe rtility s u rv e y u n d e rta k e n th ro u g h o u t N o rth ern Ire la n d in 1983, b a sed on a sample of 3000 e v e r-m a rrie d women an d th e ir p a r t n e r s , allows more rec e n t tr e n d s to be in v e s tig a te d . Some of th e prelim inary re s u lts of th e s u rv e y a re re c o rd e d in T able 3.8 an d in th is case five se p a ra te a re a s a re given in relation to av e ra g e com pleted family size. It is a p p a re n t th a t th e d iffe re n c es in family size betw een Roman C atholics an d non-Rom an C atholics a re still v e ry d istin c tiv e an d fo r b o th o f th e se g ro u p in g s th e re is a q u ite m arked sp atial g ra d ie n t of fe rtility . For exam ple, a v erag e family sizes a re g en erally sm allest am ongst th e population living bey o n d th e immediate B elfast s u b u r b s , 90

F E R T IL IT Y P A T T E R N S IN T H E MODERN WORLD

T a b le 3 . 8 : V a r i a t i o n s i n f a m i l y s i z e i n N o r t h e r n I r e l a n d by a r e a and r e l i g i o n , 1983. ( E v e r - m a r r i e d women ag ed 4 5 -5 9 )

Area B elfast B e l f a s t S uburbs I n n e r Zone: F r i n g e B e l f a s t I n t e r m e d i a t e Zone O u ter Zone: West o f t h e Bann

Roman C ath o lic 4 .0 3 .7 3 .3 5 .2 5 .4

Non-Roman C ath o lic 2 .4 2 .6 2 .2 2 .7 3 .2

S o u rc e : N o r t h e r n I r e l a n d F e r t i l i t y S u r v e y , 1983.

somewhat g re a te r in th e in term ed iate frin g e a re a s and p a r ­ ticu larly la rg e am ongst th e more ru ra l p o p u lations in the w estern h alf of th e p ro v in c e . F u r th e r a n aly sis will be able to confirm th e e x te n t to which th is g ra d ie n t is a p ro d u c t of certain compositional v a ria b le s such as social c la s s , e d u c atio n , housing and female a c tiv ity , o r w h eth er it is in flu en ced by o th e r fa c to rs such as th e diffu sio n of th e small family ideal from th e more developed e a st to th e le ss developed w est. The example of N o rth ern Ire la n d th e re fo re p ro v id es a su itab le illu stra tio n of m arked v a ria tio n s in fe rtility in (re lativ ely small) developed a re a s and th a t th e se a re ev id e n t ev en at fairly co arse levels of a g g re g a tio n . CONCLUSION The c h a p te r h as em phasised some o f th e c h a ra c te ris tic s of contem porary fe rtility p a tte r n s fo r a v a rie ty of d iffe re n t scale levels an d from th e exam ples cited h e re it a p p e a rs th a t v a ri­ ations in fe rtility a re most ev id en t to w ard s th e extrem es both micro and macro - of th e scale continuum . Given th e relativ e neglect of fe rtility stu d ie s b y g e o g ra p h e rs, fu tu re re se a rc h will hopefully c o n trib u te to th e co n tin u ed docum en­ tation and m onitoring of sp atial fe rtility p a tte r n s th ro u g h o u t th e world at a v a rie ty of sc a le s, as well a s c o n trib u tin g to methodological developm ents b y , fo r exam ple, exam ining a w ider ran g e of fe rtility in flu en cin g v a ria b le s, m aking g re a te r use of in d iv id u al d ata as well as a s s e s s in g th e role of g en eral models of fe rtility change an d d ecline.

REFERENCES B o seru p , E. (1984) 'S h ifts in th e D eterm inants o f F e rtility in th e D eveloping World: E nvironm ental, T ech n ical, Econ91

FERTILITY PA TT E R N S IN THE MODERN WORLD

omic and C ultural F a c to rs,' P aper p re se n te d at B .S .P .S . Annual C onference, Cambridge Caldwell, J . (1977) 'T he Economic Rationality of High F er­ tility : An Investigation Illu stra te d with N igerian Survey D ata', Population S tu d ie s, 31, 5-27 Caldwell, J . (1981) 'T he Mechanisms of Demographic Change in Historical P e rsp e c tiv e ', Population S tu d ies, 35, 5-27 Caldwell, J (1982) 'T he Failure of T heories of "Social and Economic Change to Explain Demographic C hange', R esearch in Population Economics, 4, 297-332 Campbell, IT (1984) Wigan Pier R evisited: Poverty and Politics in the 1980's, Virago P re ss, London C larke, J . (1977) 'Population G eography', P ro g ress in Human G eography, 1, 136-41 C larke, J . (19847 'Islamic Populations: A S y n th e sis,' Paper p re se n te d at I.B .G . Annual C onference, Durham Coale, A. (1967) 'F acto rs A ssociated with th e Development of Low F e rtility : An H istoric Sum m ary', World Population C onference 1965, 2, 205-209 Compton, P. (1978a) 'F ertility D ifferentials and th e ir Impact on Population D istribution and Composition in N orthern Ire la n d ', Environment and P lan n in g , A, 10, 1397-1411 Compton, P. (1978b) N orthern Ireland: A C ensus A tlas, Gill and Macmillan, Dublin Coward, J . (1978) 'C hanges in th e P a tte rn of F ertility in the Republic of Ire la n d ', Tijd. voor Econ. en Soc. Geog. 69, 353-61 Coward, J . (1980) 'V ariations in Family Size in th e Republic of Irelan d ', Journal of Biosocial Science, 12 ( 1 ) , 1-14 Coward, J. (1982) 'F ertility Changes in the Republic of Ireland D uring th e 1970's', Area 14 ( 2 ) , 109-117 Coward, J . (1985) 'T he Spatial P erspective in th e Study of Fertility and M ortality', in R. Woods and P. Rees ( e d s .) , Developments in Spatial D em ography, George Allen and Unwin, London C u trig h t, P. and Kelly, W. (1981) 'T he Role of Family Plan­ ning Program s in F ertility Declines in Less Developed C o u n tries', 1958-1977, International Family Planning P erspectives 7, 4, 145-151 E b erstad t, N. 0-980) 'R ecent Declines in Fertility in Less Developed C ou n tries, and What "Population Planners" May Learn From Them ', World Development 8, 37-60 E versley, D. (1982) 'Demographic Change and Regional Policy in the United Kingdom', in D. E versley and W. Koilman ( e d s .) , Population Change and Social Planning , 349-373, Edward A rnold, London F resh b ach , M. (1982) 'T he Soviet Union: Population T ren d s and Dilemmas', Population B ulletin 37, 2, Population R eference B ureau

92

FERTILITY PATTERNS IN THE MODERN WORLD Fuller, G. (1984) 'Population G eo graph y a n d Family P la n n in g ', in J. C larke ( e d . ) , G eo graph y a n d P o p u latio n , Pergam on, Oxford Gittins, D. (1982) F a ir Sex: Family Size a n d S t r u c t u r e , 1900-39, H utch in son , London H a rriso n , P. (1979) 'P o v e r t y a n d P op ulation', New S o c ie ty , 5 J u l y , 9-11 H uang, L. (1982) 'P lan n e d F ertility of One C ouple-O ne Child Policy in th e People's R epublic o f C h in a ', J o u r n a l of Marriage an d th e Family, 775-784 H u ss, M. (1986) 'D e m o gra ph y, Public Opinion an d Politics in F ran ce 1974-80, Occasional P a p e r No. 16, D ept, of Geo­ g r a p h y , Queen Mary College, London Illsley, R. an d Gill, D. (1968) 'C h a n g in g T r e n d s in Illegit­ imacy', Soc. Sci. a n d Med. 2, 415-33 In ternation al Planned P aren th o o d F e d era tio n (1982) 'Islam a n d Family Plan nin g Leaflet 1/82, IPPF, London Jagielsk i, A. (1980) 'U rb a n isa tio n a n d Spatial A sp e c ts of "Demographic T ra n sitio n " Oeconomica Polona, 1, 84-104 J o n e s , H. (1975) 'A Spatial A nalysis o f Human F e rtility in Scotland, Scot. Geog. Mag, 91, 102-113 J o n e s , H. (1981) A Population G e o g r a p h y , H a rp e r a n d Row, London J o n e s , H. (1984) 'Population G eography in B r it a in ', in J . Clarke ( e d . ) , G eo graph y a n d P o p u la tio n , Pergam on, Oxford K e nn edy , R. (1973) The I r is h : M arriage F e rtility a n d Emi­ gratio n , U n iv ers ity o f California P r e s s , London Koilman, W . and C astell R u d e n h a u s e n , A. (1982) 'P a s t and P re s e n t Policy Reactions to F ertility Decline in G erm any ', in D. E v ersle y an d W. Kollman ( e d s . ) , Population C hange and Social P la n n i n g , E dward A rn o ld , London, p p . 414-24 L ig h tb o u rn e , R. S in g h , S. G re e n , C. (1982) 'T h e World Fertility S u r v e y : C h a r ti n g Global C h il d b e a r in g ', Popu­ lation Bulletin 37, 1, Population R e fe re n c e B u reau M urphy, M. an d S u llivan, O. (1983) 'H o u sing T e n u r e in F e r ­ tility in P o st-w a r B r it a in ', C e n tre f o r Population S tu d ie s R esearch P a p e r No. 83-2 OPCS (1984a) G eneral Household S u r v e y , 1982 HMSO, London OPCS (1984b) 'OPCS Monitor: C onceptions In s id e a n d O utsid e M arriage, 1969 to 1981', R e feren ce FMI 84/86, OPCS, London O v erto n , E. (1982) 'T h e Decline in F ertility Since 1964', in D. E versley a n d W. Kollman ( e d s . ) , Population C h an g e a n d Social P la n n i n g , Edw ard A rn o ld , L ondon, p p . 20-61 Population R eference B u re a u (1984) '1984 World Population Data S h e e t', P . R . B . , Washington D .C . Rees, P. (1981) 'Population G e o g ra p h y ', in N. Wrigley a n d R. B en n ett ( e d s . ) , Q u a n titativ e G e o g ra p h y : a B ritis h View, R outledge and Kegan Paul, London 93

F E RT IL IT Y PA TT E R N S IN THE MODERN WORLD

Schnell, G. and Monmonier, M. (1983) The Study of Popu ­ lation: Elements, P a tte rn s and "P ro ce sse s, M errill, Columbus, Ohio Schultz, T . ( e d .) , 1974 Economies of th e Family: M arriage, C hildren and Human C apital, U niversity of Chicago P re ss, Chicago T rew arth a, G. (1953) 'A Case fo r Population G eography', A n.A ss.A m .G eogs. 43, 71-97 Van 1

3.d

O u t s i d e sy s tem (em ig ra tio n ) (o)

T o tals ( o p e n in g sto ck s) (•)

B. Fo r t h e I n f a n t C o h o r t s (ATP2) F in a l s t a t e s I n s i d e sy stem S u r v i v a l a t end D e a th i n i n t e r v a l (s) (d)

In itia l sta te s In sid e system

B irth in in te rv a l

O u tsid e s y s te m

(im m ig ratio n ) (o)

T o ta ls

bs

(o)

(clo sin g sto ck s)

bd

O u tsid e system (e m ig ra tio n ) (o )

T o tals (o p e n i n g sto ck s) (.)

bo

od (.)

i° ° ' V ° POPULATION

V a r i a b l e s - K: a m a t r i x v a r i a b l e ; k : a v e c t o r v a r i a b l e ; k: a s c a l a r v a r i a b l e . S u b s c r i p t s - a : r e f e r s t o t r a n s i t i o n s t a k i n g p l a c e b e tw e e n an a g e g r o u p a x a t ti m e t and t h e n e x t , a x+n, a t ti m e t + n , w h e re n i s b o t h t h e ag e and ti m e i n t e r v a l ( s e e F i g u r e 1 0 . 3 , ATP2, a r e a A ). 0 : r e f e r s t o t r a n s i t i o n s t a k i n g p l a c e b e tw e e n b i r t h , o r ag e 0 , d u r i n g a ti m e i n t e r v a l and t h e f i r s t ag e g r o u p , a ^ , a t ti m e t + n . S u p e r s c r i p t s i d e n t i f y s u b m a t r i c e s by l i f e s t a t e c o m b i n a t i o n .

MODELLING

303

A. F o r e x i s t i n g c o h o r t s (ATP2)

O rig in s t a t e s I n s i d e sy s te m

O rig in s

O u t s i d e sy s te m ( i m m i g r a t i o n s )

M a ^a

T o tals (c lo sin g sto ck s)

P r aF N o te: a i s t h e age g ro up l a b e l (ATP2); a > 1.

d

d

a 0 a

O u t s i d e sy s te m (em ig ra tio n s) e

e

T o tals (o p e n in g sto ck s) I

a 0 a

Pa i t

a a

B. For i n f a n t c o h o r t s (ATP2) D estin atio n s t a te s I n s i d e sy s te m D eath D estin atio n s

O rig in s t a t e s I n s i d e sy s te m

O rigins

O u t s i d e sy s te m ( I m m i g r a t i o n s ) T o tals (c lo sin g sto ck s)

M o

do

*0

0

O u t s i d e sy s te m (em ig ra tio n s) *0 0

T o tals (o p e n in g sto ck s) b 10

eo d0 eo V a r i a b l e s - M: m a t r i x v a r i a b l e ; d : v e c t o r v a r i a b l e ; i : a s c a l a r v a r i a b l e . S u b s c r i p t s - a r e f e r s t o movements t a k i n g p l a c e a t age b etw een an age g ro u p a a t ti m e t and t h e n e x t , ®x+n* a t tim e t + n , w here n i s b o t h t h e age and tim e i n t e r v a l ( s e e F i g u r e 1 0 . 3 , ATP2, a r e a A). 0 r e f e r s t o movements t a k i n g p l a c e b e tw een b i r t h , o r age 0 , d u r i n g a tim e I n t e r v a l and t h e f i r s t age g r o u p , a ^ , a t tim e t + n .

MODELLING

D e stin a tio n s ta te s I n s i d e sy s te m D e stin a tio n s D eath

POPULATION

304

T a b le 1 0 .6 : A Demographic M a t r i x C o n n e c tin g Opening and C l o s i n g P o p u l a t i o n S to c k s i n a Time P e r i o d U sing Movement Data

P O P U L A T IO N MODELLING

Mfl

T able 10.6 term s a m atrix o i moves betw een o rig in and d estin atio n s ta te s . Moves a re classified b y s ta te befo re th e move an d s ta te a f te r th e move.

d

a column v e c to r of d e a th s classified b y o rig in s ta te , th e sta te which a p e rso n leaves on d y in g .

e

a column v e c to r o f em igrations classified b y s ta te , th e s ta te a p e rso n leaves on e m ig ratin g .

P a I

o rig in

a column v e c to r of in itial p o p u latio n s classified o rig in sta te at th e s ta r t of th e time in te rv a l.

by

i

a row v e c to r of im m igrations classified by d e stin a tio n s ta te , th e s ta te a p e rso n e n te r s on im m igration.

i

a

p

F

s c a la r, th e sum of all im m igrations in to th e sy stem .

a row v e c to r of final p o p u la tio n s, classified by d e s tin ­ ation s ta te at th e en d of th e time in te rv a l.

ea

a

t

a sc a la r, th e to tal o f all moves in v o lv in g th e system of in te r e s t.

sc a la r, th e sum o f all em igrations from th e system .

T he term s fo r th e in fa n t co h o rt are all e q u iv a le n t, excep t th a t b ir th s ta te s a re s u b s titu te d fo r e x isten c e s ta te s and o p en in g sto c k s: kQb

a column v e c to r of to ta l b ir th s classified b y s ta te at b ir th , summed o v e r m others' a g e s a t m aternity (T able 10.5B te rm ).

b

a column v e c to r of b ir th s classified by o rig in s ta te at b ir th , summed o v e r m others' a g es a t m ate rn ity .

Note th a t, a p a rt from th e o p en in g a n d closing population sto c k s, also d ire c tly e q u iv alen t a re th e two d e a th s v e c to rs , ka -d an d d a , alth o u g h th e y a p p e a r in d iffe re n t locations in th e tra n sitio n and movement acc o u n ts ta b le s . A Projection Model Given th e se d e fin itio n s, we can now develop population p ro ­ jection models in c o rp o ra tin g outflow co efficien ts th a t "su rv iv e " initial population sto ck s fo r both tra n s itio n an d movement cases. S u rv iv al eq u atio n s a re needed fo r b o th e x istin g and infan t c o h o rts, and a fe rtility model is n eed ed to g e n e ra te th e opening sto ck s ( b ir th s ) of th e in fa n t co h ort from th e p o p u ­ lations at ris k in th e e x istin g c o h o rt. T he models a re specified with exogeneous in p u ts (im m igrants o r immi­ g ra tio n s) . The closing population sto ck s a re given b y , in th e tr a n ­ sition c ase, 305

POPULATIO N MODELLING

k a ' s = 1 Kge s + k a os

( 1 0 .1)

k o ,s = l K0bS + Hobs and in th e movement case by

( 10. 2)

pa ( t + l ) = 1 Ma + i a

(1 0 .3 )

P0 (t +1)

( 1 0 . A)

where 1 is a row v e c to r of o n es. To link closing population sto c k s to initial we need to define outflow co efficien ts. In th e tra n s itio n case each elem ent in th e K es m atrix is d iv id ed b y its c o rre sp o n d in g row to ta l, initial populations for e x is tin g c o h o rts C es ~a

(1 0 .5 )

(k-e-)-1 Kaes

and fo r th e in fan t c o h o rts, b ir th s ( 10. 6 )

9abS = (bob ->_1 ?obS

where th e circum flex in d ic a te s th a t th e column v e c to rs have been sp re a d out to form a diagonal m atrix so th a t, for exam ple. 1

(k /-)-1

(1 0 .7 )

1 Kae l i i 0 K e2.. a

Kaen The outflow co efficients from th e Table 1 0 .4B exam ple would b e , for in s ta n c e , 98.5/1184.0 o r .832 for th e flow of s u r ­ v iv in g s ta y e rs w ithin th e South E ast region and 92.7/1184.0 or .078 for m igrants (s u rv iv in g ) from th e South E ast to th e R est of B rita in . T hese coefficien ts a re tra n sitio n p ro b a b ilitie s. If th e Kaes and Ka m atrices in eq u atio n s (1 0 .1 ) and (10.2) are s u b s titu te d fo r by e x p re ssio n s d e riv e d from equations (10.5) and (10.6) re s p e c tiv e ly , we obtain p ro jection equatio n s fo r th e closing population sto ck s in e x istin g co h o rts ka ' S =

I

b a e ‘ Ça e s ♦ k a °s

= k , e - ’ C e s + k os

JUG

(10.8)

P O P U L A T IO N MODELLING

and for th e in fa n t cohort k0 ‘s = I >50b - ?0bs + >50os * bob - ’ 5obs + >50os (10' 9) where th e prime in d ic a te s tra n sp o sitio n m aking row v e c to rs of initial populations o r b ir th s to ta ls. Outflow coefficients com puted by d iv id in g th e flow term by th e initial population a re a p p ro p ria te fo r th e tra n sitio n case becau se only the in itial population c o n trib u te s to the flow. In th e movement c a se , how ever, th e c o n trib u tin g p o p ­ ulations a re more v a rie d : a m igration in th e 1976-81 period from G reater London to th e R est o f th e UK could be made by a p e rso n in th e G reater London population in 1976, o r by a p e rso n who was in a n o th e r region initially and who m igrated to G reater London. The p ro p e r population at risk is th e averag e population o v er th e p e rio d . Normally, an arithm etic averag e population is a d o p ted with th e assum ption th a t the population ta k e s a lin e a r p a th betw een s ta r t and end of th e time in te rv a l. The outflow co efficients in th e movement case a r e , usin g algebraic notation of Table 1 0 .4C, ma i j = Ma i j / . 5

(Pa i - + P a - i )

ma i o = Ma i ° / . 5

(Pa i - + Pa - i )

da i

(P a i - + Pa - i )

= Da i / . 5

(10.10)

where lower case le tte r s a re u se d fo r th ese o c c u rre n c e -e x p o su re ra te s of in te r - s ta te movement w ithin th e system , of em igration to th e o u tsid e w orld, and of d e a th . These ra te s cannot be u se d d ire c tly in th e p rojection equations becau se th e ra te denom inators a re not th e initial populations. D raw ing on d e riv a tio n s by R ogers and L edent (1976), Willekens and R ogers (1978), Rees (1983b), Willekens and Drewe (1984) and Keilman (1984), th is problem can be solved in th e following way. F ir s t, we u se a lg eb raic notation and th en g en eralise th is re s u lt to a m atrix e q u a tio n . T he closing population sto ck s in an age g ro u p (ATP2) a re given by V * = pa i- ■ ( 1 Ma i j + V

+ Ma io) + £ M j i + M,oi ■j

(10.11)

•

S u b stitu tin g fo r th e in te rn a l m igration, d e a th s an d em igration term s from ex p re ssio n s d e riv e d from eq u atio n set (1 0 .1 0 ), we 307

PO PULATIO N MODELLING

obtain P*-1 = V

' ( E ma 1J + da 1 + ma io ) ( .5 ( P a1- + Pa - i) j« + Z ma j i

( . 5 (Pa j • + Pa - J ) + Ma 01

(1 0.1 2)

j^ i which is re p e a te d fo r all s ta te s i = 1 to N. T hese N eq u atio n s can be re w ritte n u sin g th e n otation of Table 10.6

in

m atrix

form ,

/ ’ - C! + -5 «a11' 1 C! - -S Ma] Ea1 ♦ [ I ♦ .5 Ma ] " l i a

(10.13)

where Ma is d efin ed as ( .4l I m_lj + da 1 + m a 1°) a -m

d

12

( £ m

o

2j

+

d

d

nl

-Ina2^

^

+ m.^o)

d

.

.

.

-m

d

n2

j*2

-ma,ln

-m„2na

( £ manj + dan + mano) j^n

T h en , if we define th e m atrix S a th u s Sa = Cl + .5 Ma ]_1 [ I - .5 Ma]

(10.15)

then th e population p ro jectio n model of eq u atio n (10.13) may be w ritten ?aF ' = ?a Pa' + '5 [ï + §a3 ¿a

(10.16)

The S m atrix is th e m atrix of outflow coefficients th a t tr a n s ­ form th e in itial o r o p en in g sto c k s in to th e fin al. Both Willekens and Drewe (1984) an d Keilman (1984) in te rp re t th e se coefficients as "p e rio d -c o h o rt tra n sitio n p r o b a b ilitie s ... th a t a p e r s o n ... classified in s ta tu s i at time t will 's u rv iv e ' u n til t + 1 ... an d at th a t time will occupy s ta tu s j ." [Keilman, 1984, p . 11]. 308

P O P U L A T IO N MODELLING

T here a re se v e ra l a rg u m en ts a g a in st th is view (see R ees, 1985, fo r a detailed case) b u t th e most fu ndam ental is th a t no amount of m athem atical m anipulation will c o n v e rt movement ra te s into tra n s itio n p ro b a b ilitie s u n le ss inform ation on th e relationship of moves to tra n s itio n s is in tro d u c e d . For th e in fa n t cohort (th o se b o rn in th e time in te rv a l) the movement r a te s a re d efin ed as diq'-j

= Mq ^-J / . 5

(B 1 + P g - 1)

mQi o = MQi ° / . 5

(B i + pQ- i )

V

(B/

= v

7-5

+ v

i}

(10.16)

where B 1 r e fe rs to b ir th s in region i (summed o v e r all ages of m o th er). D efining Mg in th e same way a s Ma , we o b tain th e system of projection eq u atio n s fo r th e in fan t cohort Pn' ( t + 1 ) CO

= Cl +

.5 ~U M - ] " 1 [ I - .5 M ] b -a + [ I + .5 M ] -1 ~o i -a

“ §0 fe. + .5 Cl + SQ] i 0

(10.17)

Willekens an d Drewe (1984) and Keilman (1984) have d iffe re n t equ atio n s for th e in fa n t cohort in which th e population a t risk for o c c u rre n c e -e x p o su re ra te s a re in c o n siste n tly d e fin e d . M odifications of th e equation s e ts fo r e x istin g co h o rts a = 1 to A a re su g g e s te d fo r th e la s t, th e A th, by Willekens and Drewe (1984) an d Keilman (1984). In fa c t, su ch modifi­ cations a re u n n e c e ssa ry if th e adju stm en t (a d d in g to g e th e r th e final p opulations of th e A - lth an d A th c o h o rt) is p o st­ poned u n til th e co n v ersio n of final p o p u lations fo r one period into th e in itial p o p u latio n s of th e n e x t. In th e tra n sitio n case th is is accom plished th u s , a tta c h in g time in te rv a l labels to th e initial an d final p opulations (q is th e c u r r e n t p e rio d , q-1 the prev io u s p erio d ) k ^ ' i q ) = k0 ‘S( q - l ) ' k ae '( q ) = ka_ 1' S( q - l ) '

fo r age group 1 fo r age groups 2 to A-I

and for th e la st age g ro u p A

’ (q) = lsA. 1*S(q-1)1 + kA-s(q-ir

(10.18)

and in th e movement case

309

P O PUL AT IO N MODELLING

X

P , (q ) ~ cl

p

= -p„ ,1 ( q - 1 ) ' .3

f o r age g r o u p s 2 t o A -l

and fo r th e last age g ro u p A P .1 « )

= PA- i F ( ' i - 1>' + P a V

»

(10.1 9)

Initial populatio ns fo r th e new p erio d in th e last age cohort A are given by a d d in g to g e th e r th e p ro jectio n s of th e la st cohort and th e la st b u t one: fo r exam ple, th e population th a t su rv iv e s from 85+ to 90+ to g e th e r w ith th a t which su rv iv e s from 80-84 to 85-89 make u p th e in itial population fo r the nex t p erio d of th e 85 an d o v e r age g ro u p . T he final ste p in th e p ro jectio n model is to in s e rt betw een th e e x istin g cohort an d in fa n t cohort projection equatio n s a se t of eq u atio n s for g e n e ra tin g th e b ir th s to tals th a t e n te r th e in fa n t cohort p ro jectio n . T he initial sto ck s for th e in fa n t cohort a re norm ally th e sum of b ir th s to m others of d iffe re n t ag es o v er th e fe rtile age ra n g e , th a t is , b.

-0

a?

u

I

kQ

(a )

( 10. 20)

a=V a2 I

b (a)

(10. 21)

a=a.

where (a) r e fe rs to th e age of m other (A T P 2). In th e projection model b ased on tra n sitio n d a ta , th e next ste p is to make th e b ir th s a function of th e initial pop u latio n s, ju s t as th e e x is t-s u rv iv e tra n s itio n s w ere so made. This assum es th a t th e b ir th s a re classified by initial location of p a re n t o r m other. T his assum ption can be d ro p p ed la te r. F ertility ra te s can be defined as Fa = ‘'a 6 ' " '

W"(a>

(10-22>

th a t is , b irth s divided by th e in itial p o p u la tio n s, w here Fa is a diagonal m atrix w ith fe rtility ra te s on th e p rin cip al diagonal. U n fo rtu n a te ly , v e ry few system s of re c o rd in g vital ev e n ts classify b irth s b y m o th er's p re v io u s life h isto ry and it would be d ifficu lt to do so. F e rtility ra te s must be defin ed by div id in g by th e a v e ra g e population in th e same fashion as th e movement projection model. In d iv id u al ie rtility ra te s a re defined in th e tra n s itio n case as 310

P O P U L A T IO N MODELLING

f 1 = K b l" / . 5 3

(K 61

3

+ K ‘'sl)

a

( 1 0 .2 3 )

a

and in th e movement case as f 1 = B 1/.5 3

3l

(P 1- + P - 1 ) 3

( 1 0 .2 4 )

3

The population at ris k (PA R ), e x p re s s e d as a column v e c to r, usin g th e lin ear assu m p tio n , a re re sp e c tiv e ly in th e tra n sitio n case PAR ~ a = .5 [k- a ' S ' + k- a e ‘ ] ~a = .5

~a

Cl + ~a

-a

+ k e *i -a

C e s , D k e *+ -a

.5 k OS -a

(1 0 .2 5 )

and in th e movement case PAR = .5 [p * ' + p *] a „a ~a = .5 = .5

CCS ~a Ca

p

[I + S ~a „a

-

+-a.5 Cl~a + i.a

S] i ] + p

p X] + .25 — -a "a

[ I + S ] i ( 1 0 .2 6 )

T h en , if a female dominant fe rtility model is ad o p te d , b irth s are g e n e ra te d , summed an d sex ed th u s kQb ‘ X = z x

I2

Fa PARa f

( 1 0 .2 7 )

PARa f

(1 0 .2 8 )

a = a.

bX

= zX

i2

a=al

~

where a s u p e rs c rip t f r e f e r s to th e female population a t r is k , w here Fa is a diagonal m atrix of fe rtility ra te s defined as in equations (10.23) o r (1 0 .2 4 ), zx is th e p ro p o rtio n o f all b irth s of sex x , and a, and a 2 a re th e y o u n g est and oldest fertile co h o rts re sp e c tiv e ly . T he b ir th to ta ls a re e n te re d in equatio n s (10.9) and (10.17) re sp e c tiv e ly to obtain th e s u r ­ vived population in th e fir s t age g ro u p b y system s ta te s at th e end of th e time in te rv a l. The projection models a re im plem ented by re c u rsio n o v e r successive time p e rio d s u sin g e ith e r fixed coefficients and immigration v e c to rs (sta b ility an aly sis - a s ex p lo red by A lexander, 1983) o r v ariab le coefficien ts and im migration v e c to rs. 311

P O P U L A T IO N MODELLING

SIMPLIFICATIONS AND COMPLICATIONS Some b r ie f re m a rk s a re made in th is co n clu d in g sectio n on some o f th e p ro b lem s faced in im plem enting th e p ro je c tio n models an d some o f th e so lu tio n s s u g g e s te d . F lexible Models In th e p re v io u s se c tio n a m atrix re p re s e n ta tio n o f p o p u latio n p ro je c tio n m odels was u s e d a s th is is th e com m onest m ethod o f e x p o sitio n u s e d . H ow ever, th e m atrix model h a s a r a t h e r rig id s tr u c tu r e fo r many p u r p o s e s , an d an a lte rn a tiv e is to d evelop a more flex ib le m odelling sy stem tie d to su ita b le so ftw a re . Full d e ta ils of th e m odelling sy stem a re g iv e n in R ees (1981) fo r tra n s itio n m odels a n d R ees (1984b) fo r movement m odels. A b rie f s k e tc h o f th e p rin c ip le s u n d e rly in g th e s e m odelling sy ste m s is g iv en h e re . T h e b a sic id e a is to e stim ate each of th e com ponents of th e a c c o u n ts m atrices (th e in d iv id u a l c ells in T ab le s 10.5 a n d 10.6) s e p a r a te ly , a n d to p ro v id e a s e t o f fo u r ch o ices fo r each com ponent. T he f ir s t choice is to e n te r flow o r sto c k d a ta fo r th e co m ponent. T h e se c o n d cho ice is to u se th e flow o r sto c k d a ta o f th e p re v io u s m odelling p e rio d . T h e th ir d choice is to e n te r r a te d a ta fo r th e com ponent along w ith a choice o f a p p ro p ria te p o p u la tio n a t r is k (in itia l o r fin al p o p u ­ la tio n s , a v e ra g e p o p u la tio n s o r m u ltista te p o p u la tio n s a t r i s k ) . T he fo u rth choice is to employ th e r a te d a ta fo r th e p re v io u s p e rio d . T h e re a re also some o th e r ch o ic es w hich e n ab le th e r e s e a r c h e r to choose b e tw e e n tra n sm issio n m odels (all th o s e in th e p re v io u s se c tio n a re tra n s m is s io n m odels) a n d adm ission m odels, a n d b etw een v a rio u s m ethods of a d ju s tin g th e a c c o u n ts m a tric e s to e n s u r e c o n s is te n c y . With s u c h m odelling sy ste m s it is p o ssib le to e x p lo re a v a rie ty of p o ssib le w ays o f clo sin g th e sy stem a n d o f e stim a t­ in g th e b a se p e rio d a c c o u n ts m a tric e s (R e e s, 1983b). Many d iffe re n t k in d s of d a ta can be u s e d . D ealing w ith a L arg e S ta te -S p a c e T h e p r e s e n ta tio n above d e lib e ra te ly did not sp e c ify w hat s ta te s w ere u s e d to c la s sify th e p o p u la tio n w ithin th e sy stem in o r d e r to re ta in g e n e ra l re le v a n c e . H ow ever, a s w as p o in te d out e a r lie r , a d o p tio n o f more th a n one o r two dim ensions in th e c lassificatio n le a d s to d iffic u ltie s of u n re lia b le , s p a r s e m a tric e s. T h re e a p p ro a c h e s to th is problem can be id e n tifie d : th e f ir s t is to decom pose o r a g g re g a te th e sy ste m s p a tia lly , th e second is to s u b s titu te r a t e s g e n e ra te d from p a ra m e te riz e d models fo r a s many o f th e model co m ponents as p o s s ib le , a n d th e th ir d is to r e s tr u c t u r e th e m odels a s m icrosim ulation m oaels at th e in d iv id u a l scale u s in g lin k e d c h a in s of p r o b 312

P O P U L A T IO N MODELLING

ability eq u atio n s re la tin g selected s e ts o f c h a ra c te ris tic s fo r an application. For exam ple, R og ers (1976) h a s shown th a t a set of models invo lv in g a region an d th e r e s t o f th e c o u n try p ro v id e a good approxim ation of th e re s u lts of a m ultiregional cohort su rv iv al model. M asser (1976) h as show n th a t h ierarch ical models of m igration c a p tu re most d etail along w ith th e g ro s s e r in te rre g io n a l flows. R ogers h as re c e n tly sum m arised h is e x te n siv e work on modelling sch ed u les of age classified m ig ration, fe rtility , fir s t m arriage and divorce in an illu s tra tiv e p ro jectio n fo r a two reg io n -fo u r m arital s ta tu s e s system fo r Sw eden (R o g e rs and Planck, 1984). Work on th e application of sp atial in te ra c tio n models in which flows a re re p re s e n te d b y a sim pler se t of orig in and d estin atio n term s and cost fu n ctio n s con tin u es apace (L e d e n t, 1981, 1985; Stillw ell, 1983) to g e th e r with work on re la te d estim ation, sta tis tic a l an d lo g -lin e a r models (W illekens, 1982, 1983a, 1983b). T he in te g ra tio n of su ch models in a m ultistate p rojection fram ew ork h a s still to be accom plished. Microsimulation m ethods (C la rk e , K eys an d Williams, 1981) have g re a t p o ten tial in en ab lin g r e s e a r c h e rs to deal with household form ation, tra n s itio n an d dissolution more effectively (C la rk e , 1985) as th e com plicated ev en t seq u en ces and in te ra c tio n s a re not co n v en ien tly r e p re s e n te d in ag g re g a te models of th e ty p e o u tlin e d . Microsimulation m ethods a re also likely to be u se fu l in solving a problem of classification p e c u lia r to system s in which an in d iv id u a l's c h a ra c te ris tic s a re in h e rite d . An exam ple would be th e eth n ic in term ix tu re th a t re s u lts from c ro s s -e th n ic m arriage and fe rtility : in th e o ry , th e possib le com binations s q u a re with each g e n e ra tio n , and to date th e problem h as been avoided in eth n ic population models (see Im migrant S ta tistic s U nit, 1979; and Ram an d R ee, 1985 for a d isc u ssio n ). Demography is not enough As Stone (1975) makes v e ry clear in h is rev iew , dem ographic v ariab les alone a re in su ffic ie n t for a p ro p e r u n d e rs ta n d in g of planned sy stem s. Population models m erely su p p ly possible p a rtic ip a n ts in sy stem s; th e decision m akers co n tro l th e activ ities and a new class of models n e e d s to be u se d th a t look at th e co sts of a c tiv itie s an d su p p ly -d em an d rela tio n ­ sh ip s. Concluding Rem arks A lthough th is c h a p te r ta k e s a p a rtia l view of population models, th e co n cep ts d isc u sse d an d th e models ex p la in ed do have consid erab le v alu e. It was shown th a t it would be perilo u s to em bark on any ex e rc ise in population modelling 313

P O PU L A T IO N MODELLING

w ithout a c le a r idea of th e n a tu re of th e system b ein g model­ led an d th e k in d of population s ta te s o r classifications n e c e ssa ry fo r th e problem in h a n d . It would also be d a n g e r­ ous not to give ca re fu l co n sid eratio n to th e ty p e of tr a n s f e r d ata th a t could be collected fo r th e system u n d e r s tu d y . It was dem o n strated th a t population models have to be designed with th e c h a ra c te ris tic s of th e tr a n s f e r d ata b e in g u se d firmly in mind. If th e se lesso n s a re app lied in th e r e a d e r's fu tu re w ork, th e n th e m istakes made by p ra c titio n e rs in th e co u rse of a rriv in g at th e u n d e rs ta n d in g s em bodied in th is c h a p te r will not have been made in v ain . REFERENCES A lex an d er, S. (1983) 'A Model of Population Change with New and R e tu rn M igration', E nvironm ent and P lanning A, 15, 1231-1257 Brow n, A. and Fox, J . (1984) 'OPCS L ongitudinal S tu d y : Ten Y ears O n ', Population T r e n d s , 37, 20-22 C lark e, M. (1985) 'D em ographic P ro cesses and Household Dynamics: A M icro-Sim ulation A p p ro a ch ', in R .I. Wood an d P .H . R ees, (e d s .) , Population S tru c tu re and Models, George Allen and Unwin, London C lark e, M ., K eys, P. an d Williams, H .C .W .L . (1981) 'M icroSimulation' in N. Wrigley and R .J . B ennett ( e d s .) , Q uan titativ e G e o g ra p h y , R outledge and Kegan Paul, London C ourgeau, D. (1980) L'A nalyse Q u an titativ e des M igrations H um aines, M asson, P aris C ourgeau, D. (1984) 'R elations e n tre Cycle de Vie et Mi­ g ra tio n s '. (R elatio n sh ip s betw een th e Life Cycle and M igration), P o p u latio n , 39, 483-514 Keilman, N. (1984) 'In te rn a l and E x te rn a l C onsistency in M ulti-Dimensional Population Projection M odels'. Working Paper N o.46, N eth erlan d s In te ru n iv e rs ity Dem ographic In s titu te , V o o rb u rg , T he N eth erlan d s L edent, J . (1980) 'M ultistate Life T ab les: Movement V ersus T ran sitio n P e rs p e c tiv e s ', E nvironm ent and Planning A, 12, 533-562 L ed en t, J . (1981) 'O n th e R elationship betw een Alonso's T heory of Movement and Wilson's Family of S patial I n te r ­ section M odels', Environm ent and Planning A, 13, 217-224 L edent, J . (1985) 'T h e Doubly C o n strain ed Model of Spatial In te ra c tio n : A More G eneral F orm ulation', Environm ent an d Planning A , 17, 253-262 Ledent, J . and R ees, P .H . (1980) 'C hoices in th e C o n stru c ­ tion of M ultiregional Life T a b le s'. Working P a p er WP80-173, In te rn a tio n a l In s titu te of A pplied System s A n aly sis, L a x e n b u rg , A u stria 314

POPULATION MODELLING Masser, I. (1976) 'T he Design of Spatial S y stem s for In te rn a l Migration A n aly sis', Regional S t u d i e s , 10, 39-52 Ram, S. a n d R ees, P .H . (1985) A Spatial Demographic A nalysis of Indians in B r a d f o r d . Working P a p e r 434, School of G e o g ra p h y , U n iv e rsity of Leeds R ees, P .H . (1979) 'Multiregional Population A n aly sis: T h e A ccounting A p p ro a c h ', Sistemi U r b a n i, 1^ 3-32 R ees, P .H . (1981) A ccounts B ased Models fo r Multiregional Population A nalysis: M ethods, P rogram and U ser's Manual. Working P ap er 295/C o m p u te r Manual HT School of G eo g rap h y , U n iv ers ity of Leeds R ees, P .H . (1983a) 'Multiregional Mathematical D em ography: Themes an d I s s u e s ' , E nvironm ent a nd P lanning A , 15, 1571-1583 Rees, P .H . (1983b) 'C hoices in th e C o n str u c tio n of Regional Population P ro je c tio n s'. Working P a p e r 378, School of G e o g rap h y , U n iv ersity of L eeds. R ep ro d u c e d in R .I . Woods an d P .H . Rees ( e d s . ) , Population S t r u c t u r e and Models, George Allen an d Unwin, London Rees, P .H . (1984a) 'Does it Really M atter which Migration Data you Use in a Population Model?' Working P a p e r 383, School of G e o g ra p h y , U niv ersity of L eeds. Forthcoming in P .E . White a n d G .A . v an d e r Knaap ( e d s . ) , Contem­ p o ra r y Is s u e s in M igra tion , Geobooks, Norwich R e e s , P .H . (1984b) Spatial "Population A nalysis u s i n g Move­ ment Data and A ccounting Methods: T h e o r y , Models, th e 'MOVE' Program a n d Exam ples. Working P a p e r 404/Comp u t e r Manual 23, School of G e o g ra p h y , U n iv ers ity of Leeds R ees, P .H . (1985) 'Developments in th e Modelling of Spatial P op ula tion s', in R . I . Woods and P .H . Rees ( e d s . ) , Population S t r u c t u r e an d Models, G eorge Allen and Unwin, London R ees, P .H . an d Wilson, A .G . (1973) 'A c cou nts a n d Models for Spatial Population A n alysis. 1: A g g re g a te P op ula tion ', Environment a n d P la n n i n g , 5, 61-90 Rogers"! A"! (1976) 'S h r i n k in g L arge-S cale Population Projec­ tion Models b y A g g reg atio n an d Decomposition', E n v iro n ­ ment and Plan nin g A , 8, 515-541 Rogers^ A. a n d L ed en t, J . (1976) 'In c re m e n t-D e c re m e n t Life T ab les: A Comment', D em o g rap h y , 13, 287-290 R o gers, A. an d P lanck , F. (1984) P aram eterized Multistate Population P ro je c tio n s. Working P a p e r 84-1, Population Program', In s tit u te of B ehavioral Science , U n iv e rs ity of Colorado, Boulder Stillwell, J . C . H . (1983) 'Migration betw een Metropolitan a n d Non-Metropolitan Regions in th e UK'. Working P a p e r 367, School of G e o g rap h y , U n iv e rs ity of L eed s, L eeds. R ep ro du ced in R . I . Woods a n d P .H . Rees ( e d s . ) , Population S tr u c tio n a n d Models, George Allen an d Unwin, London

315

P O PU L A T IO N MODELLING

S tone, R. (1971) D em ographic A ccounting and Model B u ild in g , OECD, P aris S tone, R. (1975) T ow ards a System of Social and Dem ographic S ta tis tic s , D epartm ent o? Economic and Social A ffa irs, S tu d ies in M ethods, S eries F. n o .18, U nited N ations, New York Willekens, F. (1982) 'M ultidim ensional P opulation A nalysis with Incom plete Data' in K. Land an d A. R ogers ( e d s .) , M ultidimensional M athematical D em ography, Academic P re s s , New Y ork, p p . 43-111 Willekens, F. (1983a) 'S pecification and C alibration o f Spatial In te ra c tio n M odels', T ijd sc h rift voor Economische en Sociale G eog rafie, 74, 239-252 Willekens, Fi (1983b) 'L o g -L in ear Modelling of Spatial I n te r ­ a c tio n ', P a p e rs of th e Regional Science A ssociation, 52, 187-205 Willekens, F. an d B a y d a r, N. (1983) 'F o re c a stin g P lace-to Place M igration with G eneralized L inear Models (GLM) An A pplication to U rbanization in th e N e th e rla n d s'. Working P ap er n o .42, N eth erlan d s In te ru n iv e rs ity Demo­ g ra p h ic In s titu te , V o o rb u rg , T he N e th e rla n d s. R epro­ duced in R .I. Woods an d P .H . Rees ( e d s .) , Population S tru c tu re an d M odels, George Allen an d Unwin, London Willekens, F. and D rew e, P. (1984) 'A M ultiregional Model for Regional D em ographic Projection' in H. T e r Heide and F. Willekens ( e d s . ) , D em ographic R esearch and Spatial P olicy, Academic P re s s , L ondon, p p . 309-334 W illekens, F. and R o g ers, A. (1978) Spatial Population A nalysis: M ethods and C om puter P ro g ra m s, R esearch R eport RR-V6-18, In te rn a tio n a l In s titu te fo r A pplied System s A naly sis, L a x e n b u rg , A u stria

316

NOTES ON CONTRIBUTORS

Dr M. Cadwallader, Department of Geography, University of Wisconsin, Madison, USA Dr J. Coward, Department of Geography, University of Ulster, Northern Ireland Dr P.H. Curson, School of Earth Sciences, Macquarie University, Australia Dr J . C . Dewdney, Department of Geography, University of Durham, England Dr A .J. Fielding, Department of Geography, University of S u s s e x , England Professor J. Gugler, Department of Sociology, University of Connecticut, USA Dr M. Pacione, Department of Geography, University of S tra thclyd e, Glasgow , Scotland Dr P. Rees, School of Geography, University of Leeds, England Professor D. Rhind, Department of Geography, Birkbeck College, University of London, England Dr J. Salt, Department of Geography, University College London, England Mr I. Thomas, School of Development Studies, University of East Anglia, Norwich, England Dr R .I. Woods, Department of Geography, University of Sheffield, England

317

T his page intentionally left blank

INDEX

A bortion Act 1967 138, 139 a g e -s ta n d a rd is e d f e r tility 4 ag e-tim e p la n 11, 12, 195-9, 298, 300 a ir po llu tio n 121, 123 a n ti- n a ta lis t 138 Arima 263 A ru sh a d e c la ra tio n 202 a u to re g re s s iv e m odels 10, 263, 264 behavio u ralism 2 , 28 bio-so cial d a ta 121 b ir th c o n tro l 23, 147 B ra n d t R ep o rt 62 B ritish S ociety of Population S tu d ie s 146 c a n c e rs 109, 110, 118, 119, 121, 123-4 can n o n ical c o rre la tio n a n a ly sis 10, 201, 206 c a re e r p a th 180 c a rry in g c a p a c ity 14 ce n su s 26, 35-57, 138, 145, 223, 295 -in fo rm atio n 60 - r e s u lts 229 - s o u r c e s 59 - v a ria b le s 125 C e n su s Act 1840 48 C en su s Act 1880 48 C en su s Act 1920 39, 55 C en su s fe rtility r e p o r ts 70 c e n s u s t r a c t s 3 , 48, 50, 53 c e n tra l p lace th e o ry 20, 21

ch a in m ig ra tio n 204 child m o rtality 5 , 23 see also in fa n t m ortality c irc u la r m ig ratio n 8 , 214, 215 C oale’s in d ic e s 83, 88 co h a b ita tio n 70, 77 co h o rt s u r v iv a l 12, 293, 300 Commonwealth Im m igrants Act 1962 138, 139 Commonwealth Im m igrants Act 1968 138 c o n fid e n tia lity 2 , 39, 40, 55 conjoint m easurem ent model 269, 275 c o u n te ru rb a n is a tio n 9, 151, 224-57 d e a th c e rtific a tio n 108 d e g e n e ra tiv e d is e a s e s 109, 1 2 0 , 121

d em o g rap h ic a c c o u n ts 11 d em o g rap hic g e o g ra p h y 16 d em o g rap h ic tra n s itio n th e o ry 1, 21, 2 4 -6, 6 1 -4 , 150 d em o g rap h y 1, 13, 16, 17, 26, 31 se e also h isto ric a l d em o g rap h y D ep artm en t o f th e E n v iro nm ent 145 D e p a rtm e n t o f H ealth a n d Social S e c u rity 144 d iffu sio n th e o r y 60 d ire c tio n a l b ia s 258, 271 d is ta n c e d e cay 169, 258, 264 319

D istrib u tio n of I n d u s try Act 1945 138 ecological fallacy 24 economic b ase 227 elim in atio n -b y -asp ects model 276 empiricism 1, 18, 26 Employment Development Board 171 e n e rg y c risis 9 e n tro p y maximising models 272 enum eration d is tric t 2, 37-8, 40-1, 46, 50, 52 environm ental s tr e s s 19 epidemiologic tra n sitio n model 118 eq u ifin ality 24 ex ten d ed family 204, 210, 213, 215, 216 ex tra -m a rita l fe rtility 75, 77, 80, 83, 84 family b ro k e ra g e 210 family p lan n in g 3, 6, 90, 64, 67, 132-55 passim feminism 4, 90 fe rtility 1, 16, 24, 29, 37, 95-6 -b e h a v io u r 137, 138 -d iffe re n tia ls 4 -lev els 6, 138, 144, 148 -r a te s 310 - p a tte r n s 14, 22, 27, 30, 58-94 -s tu d ie s 3 see also m arital fe rtility fe rtility tra n s itio n 25 field th e o ry 10, 261 FOSDIC (Film O ptical S en sin g Device fo r In p u t to C om puters) 3, 48, 49 G eneral Household S u rv e y 60 g ra n d th e o ry 1, 24 g ra v ity models 168, 169, 177, 258, 259 g reen alliance 241 h ig h -lev el manpower 7 histo rical dem ography 95, 96 320

h isto ric a l m aterialism 61 Hoover in d ex of c o n cen tratio n 230 hum an cap ital th eo ry 264, 265 humanism 2, 28 illegitim acy 68, 83, 84, 88 im m igration 38, 53, 172, 173, 175, 311 -c o n tro ls 6, 218 -le g isla tio n 138, 139 -policy 150 Imm igration Act 1971 138, 139 im m unisation 99, 103, 106 in d e p e n d e n c e 201, 205, 207, 208 in d u s tria l re s e rv e arm y 29 in fa n t m ortality 64, 65, 97-119 passim 150, 201, 202 in fectio u s d isease 105 , 109, 124 see also w a te r-b o rn e d ise a se s inform ation field s 22 inform ation in te g ra tio n th e o ry 275 in te rn a l la b o u r m arkets (ILM) 181 in te rn a l m igration 7 -8 , 39, 194-223, 224-5, 233, 307 in te rn a tio n a l m igration 6, 7, 164-93 In te rn a tio n a l P a sse n g e r S u rv e y 177 in te r-re g io n a l m igration 10, 257-70 in te rv e n in g o p p o rtu n itie s 169 in tr a - u r b a n mobility 270-7 ischaem ic h e a rt d ise ase 97, 118, 119 K hym er Rouge 188 Koran 64 lan d ow n ership 201, 243 laten cy 120 latifu n d io s 201 lead poisoning 123 Lexis diagram s 12, 295 life e x p e c ta n cy model 293 life h is to ry ty p e s 287-9, 299

life table models 12, 300 life-w orld 29 limits to grow th 241 linkage analysis 258 Local A uthority Areas (LAAs) 37, 38, 41, 43, 44, 46 log linear models 11, 276 lum penproletariat 203 marital fertility 4, 25, 26, 75 Markov chain analysis 10, 263 marriage 21-2, 28, 65, 70, 74, 86, 117, 211-2, 313 mental maps 266-8 m icro-theory 1, 21-3 m iddle-range th eo ry 1, 23 migrant stock 259 migration 1, 6, 8, 14, 16, 22, 28, 43, 77, 96, 151-4 passim -flows 9, 18 -information 19 -netw orks 6, 7, 171-5 -p a tte rn s 27, 30 -p ro cess 11 -stu d ie s 2 -th e o ry 6, 31 see also chain migration circu lar migration in tern al migration in ternational migration in ter-reg io n al m igration re tu rn migration stage migration transm igration minifundios 201 mobilcentric 180 mobility ra te s 270-2 mobility tran sitio n 150, 224 mode of production 2, 29 modernisation 3, 23-4, 61-2, 64, 235 morbidity 121 mortality 1, 16, 24-6, 95, 148-50 -g ra d ie n ts 99 -ra te s 202 -stu d ie s 4 -v ariatio n s 14, 27, 30 see also child m ortality, infant mortality

movement accounts 294, 297 m oving-average models 203 m ulti-eollinearity 10, 260 m ulti-dim ensional sealing 10, 266, 269, 270, 275 m ulti-regional dem ographic accounting system s 26 m ulti-state tra n sitio n probabilities 11 National Health (Family Planning) Act 1967 138, 139 National Health Service 133, 143, 144, 289 neoplasms 99, 108 new spatial division of labour (NSDL) 9, 10, 244-8 norm ative-deductive theory 20 nu p tiality 68, 70, 77, 84, 88 Offences A gainst the Persons Act 1861 139 oil c risis 144, 225 OPCS Longitudinal Study 285, 289, 290 O rganisation of African Unity 183 O verseas Development Adm inistration 144 O verurbanisation 218 p a rity ra te 107 path analysis 261, 262, 268 272 p au perization 200 p eri u rb an isation 236 p ersonal c o n stru c t th eo ry 265 place p re fe re n ce 242, 244 place u tility 10, 19, 151, 265 political b a rrie rs 170-1 Population B ureau 144 population dynamics 6, 9, 16, 137, 285 population fo recastin g 17 population modelling 11, 12, 284-316 Population Panel 142, 143, 144 population policies 5, 6, 67, 132-65 321

population s tu d ie s 1, 2, 13, 95 see also B ritish Society of Population S tudies positivism 2, 27, 30 postcode se c to rs 46 p re s s u re g ro u p s 137 prin cip al com ponents an aly sis 260, 275 p ro -n a ta lis t 64, 67, 138 psy ch ic co sts 264 public h ealth 109 recession 9, 200, 225, 243 re fu g e e s 6, 173, 181-9 regional secto ral specialisation (RSS) 9, 10, 244-8 reg re ssio n an aly sis 27, 259, 267, 272 re g re ssio n models 168, 169, 175, 177, 189 re p a tria tio n 181, 183 resid e n tia l mobility 10 resid e n tia l p re fe re n c e 10 resid e n tia l se a rc h 233-4 resid e n tia l s tr e s s 11, 272, 273 re tu r n m igration 4 , 7 , 90, 176, 216-7, 235 ris k fa c to rs 120-5 Royal Commission on th e D istrib u tio n of In d u stria l Population 1940 138 Royal Commision on Population 1944 138 SASPAC 3, 46 school d is tr ic ts 3 second homes 242 secularism 4, 90 sem antic d ifferen tial tec h n iq u e 265, 275 sh ift-s h a re an aly sis 245 single equation models 259-61 SMSAs (S ta n d a rd M etropolitan S tatistical A reas) 3 small a re a s ta tis tic s (SAS) 3, 43, 46 social p h y sic s 6, 168, 169 social w elfare 9 stag e m igration 204, 205 322

s ta n d a rd is e d m ortality ratio s 4, 98, 112, 119 sto p p in g ru le s 274 s tr u c tu r a l equ atio n models 261-2 stru c tu ra lism 2, 18, 28 s tru c tu ra tio n 29 su b u rb a n isa tio n 9, 225, 227, 239, 240 su icid e 106, 110, 119, 121 su n b e lt 9, 229, 234, 247 th e o ry and methodology 13-34 tim e -se rie s te c h n iq u e s 263 to tal fe rtility ra te 65, 68, 88 Town an d C o u n try Planning Act 1947 138 tra n sitio n acco u n ts 294, 296 tra n sm ig ra tio n 194 T re a ty of Rome 177 tre n d su rfa c e an aly sis 271 u n d e rb o u n d in g 229, 239, 240 u n d e rc o u n t 55, 56 underem ploym ent 195, 216 u n d e r-e n u m e ratio n 59 U niversal D eclaration of Human R ig h ts 171 u rb a n -b ia s 8, 148, 203 u rb a n job lo tte ry 8, 209 u rb a n la b o u r m arket 206-8 u rb a n tra n sitio n 194, 195-200 w a te r-b o rn e d iseases 125 w estern isatio n 61, 64 work p erm its 170 World Bank 137 world economy 78, 199, 200, 225 World F e rtility S u rv ey 60 World Population C onference 133