An experimental study of the prediction of scholastic success in colleges of law

Citation preview

AM SXmmmTAL stum 0P the feeeictiqh op scholastic success W COLLEGES OP LAW

W i 11 \a.

Michael M a m s

4 dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, in the Department of Psychology, in the Graduate College of the State University of Iowa July, 1942

ProQuest Number: 10592882

All rights reserved INFORMATION TO ALL USERS The quality o f this reproduction is d e p e n d e n t upon th e quality o f th e copy submitted. In th e unlikely e ven t th a t th e author did not send a c o m p le te manuscript and there are missing pages, these will b e noted. Also, if m aterial had to b e rem o ved, a no te will indicate the deletion.

uest ProQuest 10592882 Published by ProQuest LLC (2017). Copyright o f th e Dissertation is held by th e Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C o d e Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 - 1346

AcsBmEmnw fhe writer wishes to express M s sincere appreciation to Or. Dewey B. Stuit for hi© invaluable advice and encourage­ ment, to Bean Mason Ladd for hi® kindly cooperation throughout the course of this investigation, to Dr* Leh&n &• funks for hi® capable assistance in preparing several sub-tests of the exper­ imental test battery, to the authors of the Ferscm-Stoddard Law Aptitude laeaiaimtion for permission to include one part of their examination in the experisnantal test battery, and to the facul­ ties of the eight collets of law who cooperated in the aptitude test experiment.

table or GOfSCTXS Chapter

rage

X

Introduction • » • * • * * • • * * * » • ♦ • • # • « Nature of the Problem . . . . . . . . . . . . . Results of Other Investigations . . * « . . » •

X X X

XX

the legal Aptitude Test Experiment introduction* . . . . . . . . . . . . . . . . . ......... Aptitude Analysis Construction of the Experimental Test Battery • Description of the Experimental Test Battery. . Administration of the Test Battery to the Experimental Group* . . . . . . . . . . . . . . Preliminary Statistical Treatment of the Test Results....... . . . . . . . .......... * • Distribution of Raw Scores on the Esqserimental Test Battery. Item Analysis for Determination of Internal Consistency • • • • • • • • • • • • . • • • • • Reliability of the Experimental Test Battery. • Validity of the Experimental Test Battery . . . Multiple Correlation between the Criterion and Sub-tests of the Experimental Test Battery. • •

IS 15 15 16 16

XXX

XV

IS 19 El 28 57 58 45

An Investigation of other Indices of Xaasr School Aptitude Introduction. . . . . . . . . . . . . . . . . . Procedure • • » • • • « . . . . . . • • • • . . Results . . . . . . . . . . . . . . . . . . . .

46 46 46 48

Summary and Conclusions. • • • • • * . . .

55

Bibliography............. *

68

Appendix: A . . . . . . . . . . . . .

........

60

Appendix B . . . . . . . . . . . . .

........

62

Appendix C . . ..........................

76

Appendix D . . . . . . . . . . . . . . . . . . . . .

85

-dv-

TABLE OP TABLES Table X

Bag© Performance of Tr&stmmi Students In Different Colleges of Laar on the Experimental^ Edition of the 1mm Legal

Aptitude Test « • XI

XXX I?

V VI VII VHI

....................

Intercorrelation® of the Total and Smb-Test Unweighted Bair Scores on the Experimental Edition of the lows legal Aptitude Test • • • • • • . . ............ * * * * * 20 Performance of the X&perimental Group on the Experimen­ tal Edition of the Iowa Legal Aptitude Test . . . . . . Items in Experimental Edition of the Iowa Legal Apti­ tude Test which Failed to Satisfy the Criterion of Internal Consistency*. . . . . . . . . . . . . . . . . Difficulty of the Items in the ^jqperimental Edition of the Iowa Legal Aptitude Test* . . . . . . ............

XX XII

22

SO 51

Percentage of Items Falling Within and Outside Theoret­ ically Optimum Bangs of Difficulty.

52

Reliability of the Experimental Edition of the Iowa Legal Aptitude Test . . . . . . . . . . . . . . . . . .

57

Correlations between Measures of First B&mster Law School Achievement and Performance on the Experimental Edition of the Iowa Legal Aptitude Test...........

59

IX Ihtercorrel&tions between Measures of First Semester Law School Achievement and Part and Total Scores on the Experimental Edition of the Iowa Legal Aptitude Test* ........ X

20

41

Correlation® between Measures of First Year Law School Achievement and Performance on the Experimental Edition of the Iowa Legal Aptitude Test

43

Number and Percentage of Students Selected from Various Freshmen Classes in the College of Law* * . * . ♦ . . .

47

Student Performance in the Iowa qualifying Examination and Pre-Law Work. .........

48

XXXI Correlation of the Predictive Indices with the Crite­ rion* . . . . . . ......... . . . . . . . .

49

TABLE OF TABLES (continued)

Table

Page

XI? Relationship between Total Pre-Law Grade Point Averages and Rank In First Tear Law Claes . . . . . . . . X? Distribution of Unweighted Haw Scores on the Experi­ mental Edition of the Iowa Legal Aptitude Test for 250 Subjects in Bight Colleges of Law . * .......... ♦ . XVI

Percent of Successes on Each Item for Highest Third and Lowest Third of 250 Subjects# the Difference In Percent­ ages, Certain Critical Ratios, and the Index of Diffi­ culty for each Item.......... . . . . . . . . . . . . .

50

61

65

TABLE OF FIGURES Figure

F&ge

1 Retribution of tor Scores for Part 1

• 28

a

Distribution of

Raw

Score®

for

Part & * • * » • » ♦ * » • 28

3

Distribution of

Raw

Scores

for

Part 3

4

Distribution of Raw Scores for Part 4

$

Distribution of Raw Scores for Part 5 « . • • « * • • • •

©

Distribution of Haw Scores for Part 6

, 25

7

Distribution of Raw scores for Part 7

• 26

5

Distribution of Raw Scores for Part 8

. 26

24 » M 25

9 Distribution of Total Haw Scores for Entire Experimental .................. Test Battery*

27

10

Distribution of Difficulty of Items in Part ! * • * . * •

34

11

Distribution of Difficulty of Iteras in Part £ • » • • • •

34

12

Distribution of Difficulty of Items in Part 3 * . . . * *

34

IS

Distribution of Difficulty of Item® in Part 4 * • • • • •

34

14 Distribution of Difficulty of Items in Part r, . . . . . .

35

15 Distribution of Difficulty of Items in Part 6 . . . . . .

35

16 Distribution of Difficulty of Items in Part 7

......... 35

17 Distribution of Difficulty of Items in Part 8 . . . . . .

35

18 Distribution of Difficulty of Items in Total Test Battery • • • « • .............

36

CHAPTER I INTRODUCTION Nature of the Problem The purpose of the present study was to determine the validity of various indices for the prediction of scholastic success in law* Specifically* the research described in this paper involved (1) the construction* preliminary validation* and tentative revision of a test designed to measure certain Intellectual characteristics considered most essential to successful law school performance* and (2) a sta­ tistical evaluation of the validity of pre-law grade point averages and scores on the Iowa Qualifying Examination as predictive indices of scholastic success in the College of law of the University of Iowa* Results of Other Investigations A review of the relatively meager literature on the prediction of law school achievement reveals that practically all previous research on this problem has been sponsored by individual colleges of law with the immediate objective of discovering better methods of selecting stu­ dents for admission. With a few notable exceptions these studies have been casual and sporadic* lacking the continuity of experimentation which is normally required for the development of highly valid and re­ liable prognostic indices* The fact that the reports of these studies have usually been rather inadequate from a statistical standpoint* that the number of cases involved has generally been small* and that the populations employed have differed widely in level and homogeneity of ability from study to study* makes impossible anything but an extremely general comparison of the results* Nevertheless* the findings of these

investigations, taken as a whole, are of considerable suggestive value for educational guidance in this vital professional area* In general, studies concerned with the prediction of scholas­ tic success in law have involved an examination of the validity of on© or more of the following predictive indices*

(1) pre-law grades,

(2) standardised group tests of general intelligence, and (5) specially constructed tests of so-called *legal aptitude* • The more important of these investigations will b© briefly reviewed in the following pages. Predictive Value of Pre-Law Grades. Kandel (IS) states that the Columbia University School of Law, in a study of 2,051 students over the nine year period from 1928 to 1956, found a correlation of .41 between total pre-law college grades and first year law school achieve­ ment. This study presumably included all freshman law students regard­ less of the institution in which they received their undergraduate training. Hood (27) reported a correlation of .47 between first year Columbia Law School grades and average undergraduate grades for 50 members of the law class of 1922 who had taken all their pre-law work at Columbia University.

Jacobs (14) computed separate correlations

between first year law grades and total undergraduate grades, and be­ tween first year law grades and average undergraduate grades in certain subject matter areas for 165 Columbia University liberal arts students who entered the law school of that institution during the years 1951 to 1934 inclusive. For total undergraduate grades he obtained a correlation of .57, for average undergraduate grades in social sciences a correlation y/ of .62, for the natural sciences a correlation of .52, and for the hu­ manities a correlation of ,45.

Kidd (16) reported that the correlation® between pre-law and first year law grade® averaged about .60 in the School of Jurisprudence o£ the University of California over a period of year®.

Prosser (19)

has stated that the correlation between these variables approximates •49 for the university of Minnesota School of Law* Details of the popu­ lations on which these conclusions were based were not given. Barrell (10) found a correlation of .75 between first semester law grade® and pre-law grades for 255 male University of Illinois stu­ dent® mho entered the law school of that institution during 1955, 1956, and 1937# A comparison of the average law school grades received during the entire three year professional course and various pre-law grade point averages for 125 students who entered the University of Wisconsin Law School in 1953 was made by Husband (IS). Be obtained correlation® of .52 for total pre-law grades, #52 for grade® in social sciences, •55 for grade® in natural sciences, ,44 for grades in language®, and •52 for grades in the student*® major undergraduate field. Several studies of the value of pre-law grade® in predicting achievement in the Tale University School of Law have been published, Crawford (3) reported in 1932 that correlations between total pre-law grades and first year law grades in that institution averaged about ,50, Bo information concerning the empirical basis for this statement was given. The results of a further investigation were more adequately reported by Crawford and Gorham (4) in 1940. On the basis of the experience of the Tale School of Law with graduates of 105 different college®, the undergraduate junior year average grade® of 749 student® In seven freshman law classes from 1951 to 1937 were adjusted so a® to

4be fairly comparable to one another* The correlation between these adjusted junior year undergraduate grades and first year law grades was found to be *55* However* a similar study involving 118 students in the freshman class of 19S8 yielded a correlation of only *34 between these variables* The authors point out that this attenuation of the coefficient of correlation was probably attributable to an increased homogeneity of ability of the class* since the criteria for admission had become more rigorous over the eight year period of the study* When this latter group of 118 students was broken down in terms of the adequacy of the data on the basis of which the junior year undergraduate grades were adjusted* marked differences in the predictive value of this indess were found* For SO students who had matriculated at Tale as undergraduates the correlation was *60* In the case of 67 students from colleges for which a fairly reliable basis of adjustment was available the correlation was *4E* while for El cases from colleges for which data for undergraduate grade adjustment was unavailable or very inadequate the correlation was only *16* Although little confidence can be placed in the absolute values of these coefficients, the general trend is similar to that found in roughly comparable studies* namely* that pre-law grades are fairly valid for predicting scholastic achieve­ ment In a given law school for students drawn from the undergraduate college of that school* but that the predictive value of such grades Is considerably lower in the case of students entering the law school from other undergraduate institutions* This phenomenon would naturally be expected in light of our knowledge of the low degree of comparability of grades assigned by different educational institutions.

-5Predictive Value of General Intelligence Teats* Relatively little data are available on the prognostic value of group tests of general intelligence for law school performance.

Crawford (5) has

reported that first year law grades and scores on the Thorndike CAVD Test* correlated from around .30 to as high as *55 for different fresh­ man classes in the Xale School of Law. This test has the disadvantage of requiring approximately four hours to administer, involving con­ siderable labor in scoring, and costing seventy-five cents a copy. A short form of Intelligence test, devised by J. Crosby Chapman and re­ quiring twenty minutes testing time, was found to yield an average correlation of about .40 with first year law grades. A combined index, comprising pre-law grades and scores on these two intelligence tests, correlated about .72 with first year law grades for Tfale students and •60 for students from other undergraduate colleges* The populations involved were not described by Crawford* Husband (1$) obtained a score of *59 between scores on the American Council on Education Psychological Examination and the average grades obtained by 125 students during the three year law course in the University of Wisconsin. Eagleton (5) reported that the correlation between scores on the same test and first year law school averages was •54 for 117 students who entered the freshman class of the University of Chicago Law School in 1950* Kidd (16) has stated that correlations of *44, *52, ,50, and *60 were found between scores on this test and first year law grades for four successive freshman classes in the University of California School of Jurisprudence.

The number of cases

on which these latter correlations were based was not stated* Hiker and Gaudet (20) report the results of a study in which

W0'O* the Dearborn Group Test (Examination C) and the Otis Self-Administering T«st of Mental Ability (Form D) were administered to 180 students entering the New Jersey Law School,

The total scores on the Dearborn

test correlated ,20 with first year law grades# *13 with second year law grades# ,10 with third year law grades, and ,18 with law grades for the entire three year period. The corresponding correlations for the Otis test were ,£6, #18* *16, and *£6# Predictive Value of Special Tests of Legal Aptitude* Dean Seashore (21) pointed out in 1924 that specialised examinations, de­ signed to measure the particular abilities required for mastery of a single subject or field of knowledge, should prove superior to tests of general intelligence for the purpose of prognosis and placement at the college level* In accordance with Dean Seashore *s suggestion* G, D. Stoddard and M, L* Person constructed a test designed to measure the specific abilities which they felt were most essential for success in law school courses.

The first edition of this test, since known as the Person-

Stoddard Law Aptitude Examination, was published in 1925,

This edition

included the following sub-tests: (1) capacity for accurate recall* (2) reasoning by analogy# (5) reasoning by analysis, (4) skill in pure logic* (S) reading comprehension. The total test comprised 85 items and required 68 minutes actual testing time. The only study of the validity of this first edition was reported by Stoddard (25), who found a correlation of *547 between the total test scores and first semester law school grades and a correlation of ,559 between total test scores and first year law grades for 100 students in the College of Law of the University of Iowa, Correlations between first semester grades and

scores on the five sub-tests seres

(1) #26# (a) *45, (3) .26, (4) .40,

and (5) *44. Correlations between first year grades and scores on the sub-tests were:

(1) *54, (2) .49, (3) *S0, (4) *41, and (5) .25*

On the basis of their experience with the first edition and a slightly modified second edition, the authors published a third edition in 1927. In this last edition the third sub-test of the earlier editions, reasoning by analysis, was eliminated and the second, reasoning by analogy, was somewhat lengthened. This edition, on which all subse­ quent studies of the test*a validity and reliability have been based, contains 90 items and requires 58 minutes of actual working time. In Fart 1 the examinee is allowed 4 minutes to read a brief Judicial opinion. At the end of the examination, 50 minutes later, he is tested for recall by means of multiple-choice questions covering the material read. In Part 2 the examinee is requested to read a second Judicial opinion and, Subsequently, to answer true-false questions concerning what he has read, to indicate the analogous points in a second hypothetical case, and to state the relevancy of certain facts In the original case to the hypothetical case. Fart 5 contains the only items which do not have a legalistic aspect. The examinee indicates the truth or falsity of stated conclusions to given premises. This sub-test is designed to test ability in syllogistic reasoning. In part 4 the examinee is asked to indicate, in a difficult Judicial opinion, the marked passages which contain answers to certain questions. This is primarily a test of reading comprehension. According to Biker and Gaudet (20), Gaudet and Marryott obtained a correlation of .42 between the total scores on the FersonStoddard test and first year law grades for 246 students in the

-8New Jersey Law School. Since Gaudet and Marryott (8), In their origi­ nal report of this research# in 1950# state that their findings were based on a smaller group than that used by Stoddard# i.e.# 100 cases# there appears to be some disagreement as to the actual number of eases on which this correlation was obtained. In 1950 Witham (26) published the results of an investiga­ tion of the Feraon-Stoddard examination conducted at the University of Tennessee Law School. From the data presented a correlation of •54 was obtained# by the present writer# between test scores and first year grades for 64 students. Eagleton (5) in 1932 reported that a correlation of .49 was found between total scores on the Ferson-Stoddard test and first year law grades for 117 students in the University of Chicago Law School. Correlations between first year grades and each of the four parts were:

(1) .15# (2) .52# (5) .34# (4} .58* The reading compre­

hension sub-test thus appeared more valid than the test as a whole. 1/Shen the scores for this group on the four parts of the Fersan-Stoddard test were combined with the scores for the same group on the five parts of the American Council on Education Psychological Examination# a mul­ tiple correlation of .62 with first year law grades was obtained. In 1959 Harrell (1) reported a correlation of .46 between first semester law grades and total scores on the Ferson-Stoddard test for 235 University of Illinois undergraduates who entered the law school of that institution over a period of three years. Correlations between first semester law grades and each of the parts of the test were:

(1) .03, (2) .38# (5) .22, (4) .35. & multiple correlation of

.78 was obtained between first semester law grades and a combination

of test scores and pre-law grades for the group studied. The most recent study of the validity of the Ferson-Stoddard test was conducted by Biker and Gaudet (20) who obtained a correlation of only .54 between total score® on the test and first year law grades for 180 students in the New Jersey Law School. the first year grades and the sub-tests weres

Correlations between (1) .29# (2) .54#

(5) #81# (4) .15. In this Investigation the test of reasoning by analogy appeared as valid as the total test. Although the Ferson-Stoddard Law Aptitude Examination is the only specific prognostic test for law school achievement which is available for general distribution# a number of individual law schoble have devised somewhat similar tests in an attempt to secure a more reliable and objective basis for selecting students for admission. Since 1958 Columbia University School of Law ha® used a test of legal capacity as one of the criteria for admission. This test# constructed by Thorndike# consists of the following parts*

(1) muti­

lated sentences# (2) English vocabulary# (5) arithmetic problems# (4) number series completion or evaluation of complicated aliquot parts fractional expressions, (5) reading of easy material of about college entrance difficulty# (6) reading of difficult material. This test comprises 576 items, requires four hours to administer# and is completely non-legal in character. The test is not available for general counselling purposes but may be used by other law schools. Since scoring is not completely objective all tests must be returned to Columbia University to be scored. A fee of $2.50 per examinee is made for test blanks and scoring service. The only available indica­ tion of the teat's validity is a correlation of .575 between the test

scores and first year lair grades for an unstated number of Columbia Lair School students reported by Kandel (IS)* Prosser (19) states that the University of Minnesota School of law experimented with a test of legal aptitude over a period of five years, from 1935 through 1957* Correlations with first year law grades as high as *62 were obtained with this testj but Prosser implies that the test-criterlon correlation tended to bo somewhat lower than this over the period of the study* The multiple correlation between first year law grades and the combined test scores and pre-law grades averaged about *64* Over 100 cases were studied each year. The 1957 edition of this University of Minnesota Test in Law was composed of six sub-tests designed to measure the following factors t (1) ability to detenaine the relevancy of statements of fact or propositions of law to a given case* (2) English vocabulary, (5) memory for legal material, (4) reading comprehension, (5) ability to state the legal principle common to Several stated court decisions, (6) mathematical reasoning. The test contained 278 items and required approximately two hours to administer. Several of the sub—tests were of the limited essay type and could not be scored objectively, According to a private communication received by the writer from Professor John E. Tracy of the Law School of the University of Michigan, that institution has experimented with a legal aptitude test since 1956, The most recent edition of this test consists of five parts*

(1) reasoning by analogy, (2) skill in pure logic, (5) ability

to state the legal principle common to several given court decisions, (4) ability to determine the relevancy of propositions of law to a given case, (6) ability to determine the applicability of a general

legal principle to given feet aituationa.

this University of t&chlgan

Legal Aptitude Test comprises 95 items and requires two hours of actual

testing time* A correlation of *60 was obtained between the total test scores and first year law grades for 205 students who entered the Uni­ versity of Michigan Law School in the fall of 1940* Correlations between the first year grades and the sub—tests for this group were:

(1) *57,

(2) *40, (5) *52, (4) ,47, (5) ,58. Part 1, which yielded the highest correlation with the criterion, is a slightly abbreviated form of Part Z of the Ferson-Stoddard test.

Part Z consists of 10 items taken from

Part 5 of the Ferson-Stoddard test* The remaining parts were adapted from the Minnesota test. One of these latter tests, Part 5, is of the limited essay type and hence cannot b© scored with complete objectivity* In 1957 the School of Jurisprudence of the University of Cali­ fornia adopted the California Legal Aptitude Test as a supplementary criterion for admission of students having a scholastic average of less than C plus in the work of their last two undergraduate years. According to Kidd (16), this test yielded correlations of *52, *64, and ,61 with first year law grades for an unstated number of cases in the entering law classes of 1957, 1958, and 1959, respectively.

Mo details of th©

nature of this test could be obtained by the present writer, probably th© most continuous and extensive experimentation with tests of legal aptitude ha® been conducted under the auspices of th© Yale School of Law,

In 1926 this school inaugurated a policy of selec­

tive admission and began experimentation with the use of tests of general Intelligence and pre-law grades in an attempt to develop a reliable and valid measure of probable success in legal studies. After several years of study of these indices, the School of Law requested the

Department of personnel Study at Yale to develop a legal aptitude test with specific reference to its particular curriculum. With the coopera­ tion of the law faculty, such a test was constructed and first adminis­ tered to the entering class of 1951. Crawford (3) states that a correla­ tion of .64 was found between first year law grades and scores on this test for the 103 students comprising this criterion group. A multiple correlation of *78 was obtained between first year law grades and a combination of test scores and pre-law grades for 99 students of this group. Annual statistical studies and item analyses of the Yale test have led to a series of revisions. The 1941 edition consisted of seven parts*

(1) verbal opposites, (2) verbal analogies, (3) logical infer­

ence, (4) mixed relations, (5) capacity for accurate recall, (6) reading comprehension, (7) ability to determine relevancy of stated legal prin­ ciples to a given case. The total test included 240 items and required 90 minutes of actual working time. Crawford and Gorham (4) reported that a correlation of .51 was found between first year law grades and legal aptitude test scores for 749 students who entered Yale Law School during the period from 1931 to 1937 inclusive. The test scores and junior f

year pre-law grade averages together gave a multiple correlation of .64 with first year law grades for this entire group. A further study, involving 110 members of the freshman law class of 1938 yielded a corre­ lation of only .55 between the test scores and first year law grades. Crawford and Gorham attribute this apparent decrease in validity of the test, from the correlation of .64 obtained in 1931 to that of .55 in 1938, to the Increased homogeneity of ability of the criterion group with which the latter coefficient was obtained. They state that, if

-13a statistical correction were made for this attenuating factor* i.e., if It were assumed that the variance for the 1938 criterion group had been the same as that for the original 1951 group, the correlation be­ tween the scores on the greatly improved test and law grades would theoretically have been *76 in 1958* Reliability of the Yale Legal Aptitude Teat, determined by the split-half method* has consistently

^

exceeded *95 for the past several years. Summary of Results of Other Investigations. Correlations between total pre-law grades and first year law grades for entire entering law classes have been found to average about .50 in several different law schools.

The correlation tends to be somewhat higher

than this value for students who receive all their undergraduate train­ ing in th© liberal aits college with which the professional school is associated and considerably lower for students who enter the law school from other undergraduate institutions.

Because undergraduate grades are

not comparable from one college to another* these grades are most valu­ able in counseling students from the undergraduate college of the law school which they expect to enter. Several standardised group tests of general intelligence have been found to have about the same value as pre-law grades for the prediction of first year law achievement.

The small amount of empirical

evidence available indicates that correlations ranging from .40 to .55 might be rather regularly expected between first year law grades and scores on the Thorndike GAVD Intelligence Test or the American Council on Education Psychological Examination in colleges of law in which no rigorously selective policy of admission is operative. Th© most promising single index of capacity for successful

-14law school performance appears to be the specialised type of examination known as the legal aptitude test* The Ferson-Stoddard Law Aptitude Examination, the original test of this type, has been used in a large number of different law schools and has been shown to compare favorably* with the better group tests of general intelligence in the prediction of law school perfomance*

More recent tests of legal aptitude have

been developed which appear to yield consistently higher correlations with first year law grades than are ordinarily found with either standardised tests of generalised intelligence or pre-law grades* Unfortunately* none of these tests is available for general use by counselors in liberal arts colleges and colleges of law who are concerned with the educational and vocational guidance of individual students. From the available evidence it would appear that the most valid quantitative index of aptitude for scholastic success in law w i H eventually be obtained from a regression equation based upon an optimal combination of total pre-law grades and scores on a perfected test of legal aptitude* It is possible that scores on the legal aptitude test alone mU l yield the best prediction for students who have taken their pre-law training at institutions other than the college of law which they expect to enter*

-ISCHAPTER II THE LEGAL APTITUDE TEST MPERXMEI'JT Introduction The purpose of the present chapter Is to describe the construc­ tion of the Experimental Edition of the Iowa Legal Aptitude Teat and to present data which have been secured preparatory to its final revision* The presentation of norms and final reliability coefficients* together with more adequate data on validity* must await the preparation of a final revised edition of the test based on further experimentation involving larger criterion groups in individual colleges of law than were available for the present study* Aptitude Analysis A careful examination of the relevant literature* supplemented by consultation with members of the faculty of the College of Law of the University of Iowa* revealed rather general agreement among authorities that certain more or less specific intellectual characteristics are especially essential to the study of law. Bingham (1), Crawford (5), Ferson (6)* Gulliver (9), Stoddard (23) and others agree fairly well that the most important of these capacities ares

(1) ability to read

difficult material rapidly and with comprehension* (2) ability to memo­ rize quickly and recall with accuracy* (5) ability to reason by analogy* (4) ability to discriminate between the relevant and irrelevant in a mass of facts* (5) skill in inductive and deductive reasoning* and (6) verbal facility* including a large available vocabulary and ability to learn new words readily* Although it is to be hoped that future research in the field of factor analysis will yield a more precis©

-16dellmitation of the primary mental abilities requisite to legal studies* it was decided that these six types of ability would be accepted as the principle ones to be measured in the proposed test battery* Construction of the Experimental Test Battery After an examination of the types of items which had proved most promising in other tests of legal aptitude* the writer* in collab­ oration with Bean Hason Ladd and Dr* Lehan K. Tanks of the College of Law of the University of Xowa* prepared a tentative battery of nine tests each of which seemed to measure one or more of the mental func­ tions in which we were interested*

On the basis of a preliminary

trial administration to a group of approximately thirty graduate stu­ dents* two of the teats were discarded as being too time consuming* and the remaining tests were revised with respect to time limits* order of Item difficulty* and elimination of ambiguous items* Since several studies had shown that the test of reasoning by analogy included in the Ferson-Stoddard Law Aptitude Examination possessed rather high validity, permission was secured from the authors for the inclusion of this test in the experimental battery* The final experimental edition of the test battery and a manual of Instructions for its administration were then prepared and mimeographed* Description of the Experimental Test Battery In order to provide an optimum basis for successful revision* it seemed advisable to allow extremely liberal time limits and to in­ clude approximately twice as many items in the tentative test battery as would be retained in the final version*

The 1941 experimental edi­

tion* therefore, consisted of eight parts comprising a total of 45S

items and requiring 260 minutes of actual testing time* Because of its length* the test was Issued in two parts to be administered in separate sessions. The following sub-tests were included* Fart 1. Amlofliea. The examinee was requested to select* from a group ofcSwords, two which bore the same relation­ ship to each other as two key words* This test was similar to those commonly employed in group tests of general intelli­ gence! but scaled at a somewhat higher level of difficulty. The test was designed to measure the student *s verbal facility and ability to reason by analogy. Part 2. Mixed Belationa. The examinee was asked to se­ lect* from a group of six words, the three which were most closely related in some way. ,Teste of this type, of a lower order of difficulty* have frequently been included in general intelligence examinations. The intention here was to measure the student’s vocabulary and ability to reason inductively In determining basic relationships• Part 5. Opposites. The examinee was required to select* from a group of five alternatives* a word opposite in meaning to a given key word. This test differed from the usual test of verbal opposites In that ability to recognise specific parts of speech as well as word knowledge was required. The purpose was to measure precision in the use of English and general vocabulary. Fart 4. Memory. Prior to taking Fart 1 the student was allowed eight minutes to study a rather detailed judicial opinion. Approximately two hours later he was asked to recall the significant facts without being permitted to refer back to the case. This was primarily a test of reading comprehen­ sion* ability to memorise and to recall with accuracy. Part 5. Relevancy. A somewhat involved ease of a legal nature was presented for study. Certain principles of law were then stated. The student was directed to accept the truth of these principles and to indicate whether each prin­ ciple would be relevant to the argument of the plaintiff, the defendant* or to neither party in the suit. This test in­ volved comprehension of difficult reading material* ability to recognize crucial points in a mass of facts* and ability to discriminate between the relevant and irrelevant. Part 6. Reading Comprehension. This test was adapted directly from the Ferson-Stoddard Law Aptitude Examination. After reading a judicial opinion, the student was required to answer questions concerning what he had read* to indicate the analogous points in a second hypothetical case* and to determine the relevancy of certain facts in the original

-18judlci&l opinion to the hypothetical case. Heading compre­ hension, ability to reason by analogy, and ability to dis­ criminate between the relevant and irrelevant were involved. Part 7. Reasoning. The examinee was required to accept a stated premise as true and to indicate whether a given conclusion was necessarily true, probably true, necessarily false, probably false, or indeterminate. The primary purpose of this test was to evaluate skill in inductive and deductive reasoning. Part 8. Information. This sub-test consisted of truefalse questions concerning common facts of law which, it was believed, students with special interest in legal matters might be more apt to acquire and retain, through incidental reading and introductory courses in history and political science, than would students whose interests lay in non-legal fields. Analogous tests employed in some of the Iowa Place­ ment Examinations had proved to have high predictive value for specific subject matter areas. Administration of the Test Battery to the Experimental Group The experimental edition of the test was administered at the beginning of the fall term of 1941 to all entering first year students in eight different colleges of law. The institutions cooperating in the experiment were; University of Cincinnati, Creighton University, Drake University, University of Indiana, University of Iowa, Ohio State University, University of Pittsburgh, and University of Tennessee. With the exception of Drake, Pittsburgh, and Tennessee, requirements for admission to these law schools were identical, i.e., a minimum of three years of pre-law work with a grade point average equivalent to that required in the liberal arts college for graduation, or a bache­ lor's degree. Drake and Tennessee required a minimum of only two years of pre-law training, with a grade point average equal to that required in the liberal arts college for graduation, while Pittsburgh required that the student must have received his bachelor's degree. Although the operation of the Selective Service Act and other factors brought

about by the war had decreased the normal freshman enrollment in most of these schools by over fifty per cent* complete test data were secured for a total of 260 cases* Frelis&nary Statistical treatment of the test Results All teste were returned to the University of Iowa where they were scored by departmental assistants and the accuracy of scoring verified by the writer*

In computing U m raw score for each sub-test*

the customary correction for chance success was made for each part with the exception of Parts 1 and 2* in which the chances of guessing success­ fully seemed too small to justify such a correction* there is seme dis­ agreement among authorities as to the value of correcting for chance success; but the concensus of opinion seems to be that when instructions against guessing are given* as in the case of the present test battery* the correction tends to raise the validity of the test* The raw scores on each sub-test were then multiplied by the reciprocal of the standard deviation of the distribution of raw test scores for that part In order to give each sub-test approximately equal weight* and the resulting weighted part ©cores were sumrnated for each examinee* The percentile rank of each student* based on the distribu­ tion of total weighted part scores thus obtained* was then computed and reported to the college of law in which he was enrolled* The mean* standard deviation, median and range of the distri­ butions of total weighted raw scores for the group tested in each coop­ erating college of law are presented In Table I on the following page. These data indicate that the various groups tested differed rather markedly in level and range of ability with respect to the composite

-2 0 -

Of intellectual functions measured by the total tost battery. TABLE

X

Performance of Freshman Student® in Blfferent Colleges of Law on the Experimental Edition of the Iowa Le;:al Aptitude fast H

M#

17 17 15 55 52 54 41 19

252.59 225.59 217.20 247.46 229.51 227.89 229,54 212.16

75.87 54.05 45.80 40.89 S5.05 62.26 68*99 60.19

250.00 255.00 219.00 240.00 219.50 220*50 255.00 2X7.00

105-561 167-282 158-551 179-555 00-565 101-400 10-541 51-556

Composite (Eight Universities) 2S0

229.58

58.52

228,6?

10-400

College of Law University of Cincinnati Creighton University Brake University University of Indiana University of Xorcna Ohio State University University of Pittsburgh. University of Tennessee

S.B.*

Range#

The intereorrei-ations between the unweighted raw scores on the eight sub-tests comprising the total test battery, and the correlation between the raw scores on each sub-test and the total raw score on the battery, based on the esperin&nt&l group of 250 cases, are presented in Table II below* TABLE II Intercorrelations of the Total and, Sub-Test Unweighted Raw Scores on the Experimental Edition of the Iowa Legal Aptitude Test#

Part 1 Part 2 Part 5 Part 4 Part 5 Part 8 Part 7 Part 8 Total

Part 1

Part 2

Part 6

Bart 4

Part 5

Part ©

Part 7

Part 8

.626 ,806 .465 .44© *458 ,528 .469 .885

.850 ,404 ,455 ,453 .480 .420 .870

*566 ,410 .587 ,481 .377 .852

,457 *437 .501 .416 *570

.470 .409 ,406 .633

,404 ,451 .821

,553 .841

.616

*Sa$ed on 250 cases in eight colleges of law

-ax-

53@S95

Application of the 8-function tost of significance suggested by Lindquist (18) indicates that the intercorrelations between the eight sub-testa of the experimental battery are all significant at better than the 1 percent level of confidence. The relatively high intereorrelatlons between Parts 1, Z9 and 3 suggest that these three sub-tests are more highly saturated with some ccmon factor or factors than are the other sub-tests of the battery,

inspection of the indi­

vidual items reveals that the single factor most unique to these three testa is one of word knowledge or vocabulary. The other sub-tests are probably all measuring reading comprehension to a greater or less degree in addition to more specific mental characteristics which they were designed to appraise. Distribution of law Scores on the Experimental Test Battery As an initial cheek, preparatory to revising the experimental test, frequency distributions of tbs unweighted raw scores obtained by the 250 subjects in the experimental group on each of the sub-tests and the total test battery were prepared. These distributions are given in Table 17 in Appendix A. The same distributions are presented graphically in Figures 1 to 9, the lower limits of the step-intervals being given on the horizontal axis for each figure. The means, standard deviations, medians and ranges of the distributions are summarised in Table XIX on the following page. Normality of the Distributions. Indices of the deviation of *a«fc of the nine attribution* from normality woro oomputoa.b* th.,.-; • •

», , !• *

*

formula given by Garrett (7). Statistically significant degrees of; negative skewness were found for the distribution of scores,oij Barts, ;

—22— TABLE XXX

Performance of the Experimental Group on the Experimental Edition of the Iowa Legal Aptitude Teat

1. 2. 5. 4, S. 6. 7. 8.

Analogies Mixed Relatione Opposites Memory Relevancy Reading Comprehension Reasoning information

Items

m

75 80 m m 50 40 40 60

50.16 34.52 26.77 17.04 24.52 28.92 14.44 30.47

S.B.* 12.15 12.91 16.56 5.33 6.64 5.95 6.32 9.13

Mdn* 50.20 55.25 25.89 18.09 25.88 23.88 14.63 31,00

Range# 050100— 00-

66 74 75 29 38 55 34 52

Total of Bight Farts 455 59.29 196,52 201.60 9-382 *Ba»ed on unweighted raw scores for 850 oases in eight colleges of law 4* 5 and 6, tending to indicate that, for the group tested, these sub-tests were somewhat too easy* The distribution of scores for Fart 5, on the other hand, exhibited a significant amount of positive skew­ ness, tending to show that tills part was somewhat too difficult for the experimental group as a whole. Moderate, but not statistically signif­ icant, degrees of positive skewness were found for Fart 2 and for the distribution of total raw scores for the test battery as a whole. The distribution for Fart 8 showed a slight negative skewness, while the distributions for Farts 1 and 7 conformed very closely to the theoret­ ically normal distribution for the number of cases involved. Since it was found that the time limits had been sufficiently liberal to permit practically all examinees to complete all of the sub-tests, the absence of scores falling in the upper range of the distributions for Farts 1, S and 8 indicates the possible presence of a few extremely difficult or ambiguous items whose replacement might improve the discriminatory value of these sub-tests*

-23-

O tO (DO >N lO O O rlT)'^O tO tO C 3>W inC O H ^, f'O lO tD O )O ilO

HHHWWWtOtOWtO'^^^lOLOLOCDtDCOtDI>'[>

Fig. 1.

Distribution of Raw Scores for Part 1

OtO(D01WWCOH^t'OtO(DO)WLOCOH'4'^OtOtO(J)WiOOD HHHWWWlOtOtOtO^rJ'^IOlOWCDCDtOtOC-^^ Fig. 2*

Distribution of Raw Scores for Part 2

-24-

OtOCDO>C2LOCOH^, l>-OtQCOO>C\iLna>r-i*a, C''OfcOCOa>C\*WOO

(HrHrHI>

Fig. 3.

Distribution of Raw Scores for Part 3

H OHWrt^WUDt-rooOHWSO^lOtDC'OOOOHWtO^LOyJf'COOlO H H H H H H H H H H W W W W W W W W W W t O Fig. 4.

Distribution of Raw Scores for Part 4

-25-

OCvi^CDCDOCJ^tDOOOC^'^COOOOC^’ H H H H H W W W C V W t O t O W^tDCOOOi^CDCOO WtO^^^^^lO Fig* 5.

Distribution of Raw Scores for Part 5

BxS OW^OOOON^tDCOOW^CDOOW^tDCOO X K

t— I i— I H > — I i— I Cvi

a

C\2 a

c\i to to to to to 'sf

Fig. 6. Distribution of Raw Scores for Part 6

X

OW^tOCOOW^tOOOOW^tDOOOW^tDCDO H H H H r l W W W W W t O W t O t O l O ^

Fig. 7.

Distribution of Raw Scores for Part 7

OcQCOO)WlOa)H^>OrtOO)Cy2lOCOH, OOCX)0^0>0

rH

Fig. 18.

Distribution of Difficulty of Items in Total Test Battery

-57Rsliability of th© Experimental Test Battery In case® where a test can be validated against a fairly reli­ able external criterion, the reliability of the test itself is a matter of secondary concern, i.e., if the test is proved valid it cannot have a low reliability* However, it seemed desirable to obtain a tentative estimate of th® relative reliabilities of the various sub-tests of the experimental battery in order that a comparison might be mad© with the reliabilities obtained with subsequent revision® of th© test. For this purpose the method designated as Gas© 17 of the series of formulas de­ vised by Kuder and Richardson (17) seemed met readily applicable. This method ha© the advantage over the customary split-half method of requir­ ing considerably less computational labor and of yielding a value which, according to th© authors, errs in the direction of conservatism, in cases in which th© underlying assumptions are not fully satisfied. The reli­ abilities of th© eight sub-tests and th© experimental battery as a whole, as estimated by this method, are presented in Table 711 below. TABLE V H Reliability of the Experimental Edition of the Iowa Legal Aptitude Test _________________ 1. Z• 5. 4. 5. 6. 7. 8.

Analogies Mixed Eolations Qpposites Memory Relevancy Beading Comprehension Reasoning Infomat ion

n 250 250 250 250 250 250 250 250

Total of ffijght Parts ... _ 250,______ ^Estimated by the Method of Kuder and Richardson, Case 27

rtt* .89 .89 .94 ,77 .75 .74 .85 .84 *07

From Table VXX it may be seen that the reliability of the teat battery as a whole is sufficiently high to justify its use for purposes of individual prognosis. Since the elimination of defective items tends to raise the reliability of a test, it would seem that a revised edition of this examination, even though somewhat sliorter, Should yield a satisfactorily high coefficient of reliability* Validity of the Experimental Test Battery Owing to factors which could not be foreseen at the time of the initiation of this project, the number of examinees for idiom measures of relative law school achievement could be obtained was unfortunately small. For this reason, the validity coefficients which are reported in the present paper must be considered as extremely tenta­ tive and of value only insofar as they suggest the general range of such values which might be expected with similar groups of examinees drawn from comparable populations. The first study of the predictive value of the experimental edition was made at the end of the first semester of the 1941-42 academic year* 2ft order that the criterion measures might be as nearly compara­ ble as possible from school to school, the following procedure was uti­ lised.

1ft each of the three colleges which had expressed willingness

to assist in this portion of the study, th© instructor of each freshman law course ranked the members of his class in order of their relative achievement during the first semester. The ranks thus assigned were converted into linear scores by the method suggested by Hull (12), weighted by the number of hours credit allowed for each course, and the resulting weighted linear scores suimaated for each student and

-39— divided by th© total number of hours credit earned* The students in each school mere tl*en reranked on the basis of these mean weighted linear scores and tli© ranks again forced into a normal distribution by application Of Hull*® method* Thus th© final criterion of first semester law school performance consisted of a single linear score for each examine© based upon th© composite ratings of the instructors in all of th© freshman law course® which the student had taken during the first half of the academic year* The validity coefficients obtained by correlating th© criterion scores for th© students in each college of law with th© total of th© weighted sub-test score® received on the experimental edition of th© law aptitude test are presented In Table fill* For purposes of comparison, the mean, standard deviation and range of total weighted sub-test scores 1® indicated for the criterion group In each college involved* TABLE fill Correlations between Measure® of First Semester Law School Achievement and Performance on the Experimental Edition of the Iowa Legal Aptitude Test College of Law

H

r

£9 *42 Uhivoroity of Indiana 42 •67 University of Iowa 59 University of Pittsburgh •77 *Based on total of weighted part scores

m 246.23 £27.52 £26.00

5,D.* 45.01 54.50 68.59

Range# 179-535 90-565 10-541

When the reliabilities of the validity coefficient® for th© three separate criterion groups were tested by th© z-function suggested by Lindquist (18) It was found that we may be confident, at th© 1 per­ cent level, that the true validity lie® between .55 and *90 for th© Pittsburgh group, between *58 and *84 for the Iowa group, and between

-40-*05 and *74 for th© Indiana group*

In terms of this rigorous criterion

of significance th® only individual coefficient of validity which can confidently be considered highly encouraging is that obtained with the group of freshman law students at the University of Pittsburgh* In order to obtain a more reliable estimate of th© validity of the experimental test, the possibility of combining th© three sepa­ rate criterion groups into a single composite criterion .group was exam­ ined.

Computation of the critical ratio® of the differences between

the means of the total weighted sub-test score® for the three groups revealed' no statistically significant difference® between these groups insofar as this measure was concerned*

However, a critical ratio of

2*66, significant at between the 1 and S percent levels of confidence, was found between the standard deviations of th© Indiana and Pitts­ burgh group®*

1b were not, therefore, Justified in assuming that all

three groups were drawn at random from identical normal population® Insofar a® performance on th© aptitude test battery was concerned* Nevertheless, since no statistically significant difference had been found between th® mean® of the test scores for the throe groups, the Inclusion of the highly homogeneous Indiana group in th© composite criterion would, according to the logic of correlation theory, tend to attenuate the validity coefficient® and thus ;rIeld an underestimate of the true validity*

three

group®.

It seemed feasible, therefore, to combine all

The coefficients of correlation between the sub-test

score® and th© criterion measures, the total test ©cores and the criterion, and th© intorcorrelauioas between th© sub-test scorer? for thi® composite criterion group are presented in Table IX on the follow­ ing page*

-41TABLE H Intercorrelations between Measures of First Semester Law School Achievement and Fart and Total Scores on the Experimental Edition of the Iowa Legal Aptitude Test# Fart \ Part 1 Fart 8 Part 6 Fart 4 Fart 5 Fart 6 Part 7 Part 8 Criterion *Based on

Fart 2

Bart 5

Part 4

•796 •807 .857 •521 •455 •448 •569 •584 .526 •408 •544 •516 .491 .527 •528 .459 •469 .418 .471 .476 •441 •405 •552 .515 •575 .401 H O oases in three colleges

Part 6

Part 7

Fart 8

Total Score

.430 .440 .618 •596 •572 .560 .456 of law

•466 •571

•462

.647

Part 5

The a-functlon test of significance indicates that we may be confident, at the 1 percent level* that the true correlation between the total of the weighted sub-test scores and the criterion lies between •49 and *77 for the composite group of 110 cases upon which the values in Table IX were based. Application of the same test of significance reveals that each of the eight parts of the experimental battery is significantly correlated, at better than the 1 percent level of confi­ dence, with th© external criterion and with every other part of the battery for this criterion group. A supplementary study, in which the "statistically identical" Iowa and Pittsburgh groups were combined to form a composite criterion group of 81 cases, yielded a correlation of .67 between the total of the weighted sub-test scores and the criterion measures of first semester law school performance. The s-funciion test indicates, at th© 1 percent level of confidence, that the true value of this latter coefficient lies between .50 and .80. A further check on the tentative validity of th© experimental test battery was made at the end of th©

1941—42

academic year.

In each

— of four colleges of law, the remaining freshman students were ranked in

order of achievement in each course which they had completed during the year and, by the procedure previously described, th© rank® were nomaliced, weighted, combined, averaged, and converted to final linear crite­ rion scores.

Zn a fifth college, the University of Indiana, it was

impossible to obtain the find ranks in individual courses? but a single numerical grade, representing the weighted average of the numerical grades in all courses completed, was available for each student. It was, therefore, necessary to compute the final linear scores for the students in this criterion group by ranking them on the basis of their average numerical grades and converting the ranks to linear scores by means of Hull*s table. Although the criterion measures thus obtained for this group were perhaps slightly less reliable, they were, for the purpose of this study, comparable in all important respects to the measures

computed for the other four colleges of law. The validity coefficients obtained by correlating the crite­ rion scores, representing first year law school achievement for the students in each of th© five college© of law, with the total of the weighted sub-teat scores received on the law aptitude test are given in Table X* Th© mean, standard deviation and rang© of th® total weighted sub-test scores ar© indicated for each of th® live criterion groups. With th© exception of tis© correlation for th® University of Cincinnati, which is significant at only the 5 percent level, th© validity coefficients presented in Table X are all significant at the 1 percent level of confidence.

However, the reliabilities of the Indi­

vidual coefficients are so low that little confidence can be placed in

-43TABLE X Correlations between Measure# of First Tear Law School Achievement and Performance on the Experimental Edition of the Iowa Legal Aptitude Test College of Law

M

r

University of Cincinnati 12 *64 University of Indiana 29 *48 42 University of Iowa •71 *69 Ohio State University 40 *76 University of Pittsburgh 28 *B##ad on total of weighted part score#

m

246.67 248.55 228.58 252.00 254.78

S.D.* 74.55 45.17 SS.17 65.14 70.65

Bang©* 121-561 178-555 80-565 101-400 10-541

their absolute value#* The s-function 'tost, applied to the four moat significant coefficient#* indicate# bliab we may be confident* at the 1 percent level* only that the true correlation lie# between *45 and *90 for th® Pittsburgh group* between .44 and .86 for th© Iowa group* be­ tween .40 and .86 for the Ohio group* and between .03 and *77 for the Indiana group. Multiple Correlation between the Criterion and Sub-tests of the Experimental Test Battery The Iherry-Doolittl© Test Selection Method described by Stead and ShartX© (22) was employed in computing the multiple coefficient of correlation between th© optimum combination of weighted sub-test score# on th® experimental aptitude test battery and the measure# of first semester law school achievement for bho composite criterion group of 110 cases previously described in this paper* Th© Mierry-DoolittXe method of multiple correlation is preferable to th© more commonly em* ployed methods in that it gives th© maximum multiple correlation after © correction has been made for the olmiee error added by each successive sub-test* thus indicating the exact point at which the addition of fur­ ther sub-tests adds more chance error than actual validity to th© teat

battery* The

multiple coefficient of correlation between the

sub-test scores and the criterion measures, as computed by the above method from the data in table XX, was found to be .67Z* The sub-tests eeleoted for inclusion in the final battery were Part 5, which corre­ lated .573 with the criterion* Part 7, which Increased the multiple correlation to *664; and Part 8, which further increased the multiple coefficient to the final value of .67$. Insofar as this particular criterion group was concerned* the addition of other sub-teste of the experimental battery added more chance error than validity to the selected test battery. The Beta weights for the three sub-tests selected by the above procedure were *348 for Part 3* .337 for Part 7, and *151 for Part 8* The regression equation for the best estimate of the criterion scores from the weighted sub-test scores of the grotto involved was* Xq * *701X$ ♦ .642X7 ♦ *287Xg ♦ 15*06* The standard error of a crite­ rion score predicted from this equation would be 14*05. In Interpreting the findings of this multiple correlation study* it must be remembered that the data on which they were based were obtained from a composite group comprised of sub-groups atdch were not statistically Identical with respect to performance on the aptitude test. Furthermore, although the criterion measures for these sub-group® were rendered somewhat more nearly comparable by the normalising tech­ nique employed than they would have been if expressed simply as numeri­ cal or letter grades, the fact that these measure® were based on ranks assigned by different instructors in three different Institutions introduce® a statistically immeasurable degree of incomparability into

the opposite criterion* the findings presented mist, therefore, be regarded as little more than suggestive of the ultimate predictive efficiency which may eventually be attained by an optimum combination of certain revised subjects based on those comprising the original experimental test battery# fhe formulation of such & final test battery must await further experImentatlon involving larger criterion groups in individual law schools than were available for the present study# It is quite probable that the optimal combination of sub-tests will vary fro® on© law school to another and that each individual school will obtain best result® by developing its own regression equation. However, there is every reason to believe that a compromise test battery can be developed which will be more valid for general counseling purposes than any other single index of potential law school performance now available*

—46**

CHAPTER X U AH XHm^TlOATIOIf OF OTHER INDICES OF LART SCHOOL APTITUDE Introduction © 4© study described in the present chapter was undertaken with the objective of discovering additional indices of aptitude for success­ ful law school achievement which might. In conjunction with the legal aptitude test described in the preceding chapter, provide a more adequate basis for advising students who contemplate entering the College of Law of the University of Iowa* Specifically, it wa© the purpose of tils investigation to determine the validity of pre-law grade point averages and scores on the Iowa Qualifying Examination as predictive indices of success in first year law at the State University of Iowa* Procedure Because of the variations in grading standards at different undergraduate colleges, only those students who had completed all of their undergraduate work at the University of Iowa and who had complete records for one year of work in the College of Law were included in the major portion of this study# These students were selected from entering d a ©see from the years 1936 to 1939 inclusive.

The number and percent­

ages selected from each class ar© presented in Table XI on the followlag page. The predictive indices available for the group of 152 students selected included grade point averages for pre-law work, and scores on the Iowa Qualifying Examination.

The Iowa Qualifying Examination, which

had been administered to all the members of this group as entering fresh­ men in the liberal art® college, consisted of the Iowa High School

**47— TABLE XX Number and Percentage of Students Selected from Various yreahman Classes in the College of Law Tear

Total Enrolled#

Total Selected

Percentage

1936 1937 1938 1939

85 96 99 107

33 38 39 42

58.52 39.50 39.39 39.93

Total 387 XS2 39.28 *The total number enrolled in each class included students who completed their pre-law work at other institutions in whole or in part, those who withdrew in the course of the year, and those registered as freshmen for more than one year Content Examination, Iowa English Training Examination, Iowa Mathematics Aptitude Test, and the Iowa Silent Beading Test. A composite score, consisting of a weighted total of the raw scores on the four examinations had been computed* The raw scores on the individual sub-tests of the battery and the composite score had been converted to percentiles and were available in this form.

It was assumed that these percentiles were

equivalent from year to year and, for purpose© of computation, the percentilea were converted to linear ©core© by use of the table prepared by Hull (13). On the basis of findings of similar studies made in other schools of law by Crawford and Gorham (4), Husband (15), mid Jacobs (14), it was decided that it might be profitable to make separate studies of the predictive value of the total pre-law grade point averages, the junior year pre-law grade point averages, the pre-law grade point averages in social science, and the pre-law grade point averages in physical sciences as well as of the ©core© on the Iowa qualifying Examination for this group.

-48* The available criterion of success In first year law consisted of a weighted total Of the numerical grades assigned In each law course completed by the student during his freshman year In the college of law* these weighted total grades were converted to ranks for each class and the ranks were converted to linear scores* These linear scores consti­ tuted the actual criterion measures utilised in the correlational anal­ ysis* Results The performance of the criterion group of 152 student® in the aptitude teste and pre-law areas studied is summarised in Table XII below.

The mean linear scores of this group on the Iowa Qualifying in«DTW i ytt lXX Student Performance in the Iowa Qualifying Examination and Pre-law Work

Predict!v© Index

H

U

s.p.

Iowa Qualifying Examinations 1* Composite Score 152

58.97

16.32

8* High School Content

XBZ

59.93

16.79

3* Mathematics Aptitude

152

58.12

18.25

4* English Training

152

53.52

16.09

£• Silent Reading

152

57.02

16.30

Bang© Linear Score 18-95 Percentile 5-99 linear Score 21-05 Percentile 7-99 Linear Score 5-05 Percentile 1-99 Linear Score 14-95 Percentile 5-99 Linear Score 11-95 percentile 2-99 1.55-3.94 1.47-4.00 1.73-5.95 1.17-4.00 1.52—3.94 1.47—4.00 1.64-3.75

.501 Total Pre-Law 0* P. A. 152 2.58 .553 2.67 Jr. Xr. Pre-Law Q* P. A* 152 .490 Soe. Sci. Pre-Law 0* P. A* 2.65 152 .647 2.47 Phy«* Sci. pre-Law 0. P. A* 152 .496 361* 2.58 Total Pre-Law 0. P. A. Jr* XT. Pre-Law 0* P. A. .538 361* 2.63 .407 Total Pre-Law G* P. A* 83** 2.65 ^ A supplementary stiidy was made of 361 students. ##A second supplementary study was made of this group of 83 students*

-49Examination and It© sub-tests were definitely superior to the scores of liberal arte freshmen as a whole* but the rang© was very wide, varying from scores corresponding to the fifth to the ninety-ninth percentile in the composite score* The mean total pre-law grade point average of 2*58 for this group was also superior to the grade point average of about 2*20 achieved by students of the College of liberal Arts as a whole* but probably not much superior to that of liberal art® seniors. Again the range is wide* extending from a grade point average of 1.55 to one of $.94. From these data it would appear that the typical University of Iowa student who enters the College of Law at Iowa Is definitely su­ perior, as a freshman, on the Iowa Qualifying Examination and maintains a somewhat bettor than average record in his liberal arts work. TABLE XIH Correlation of the Predictive Indices with the Criterion Predictive Index

11

T

Iowa Qualifying Examinations 1. Composite Score .471 152 .576 152 2. High School Content Examination .338 152 5. Mathematics Aptitude Test .418 152 4. English Training Examination .425 152 5. Silent Beading Test Pre-Law Grade Point Average®$ •668 152 Total Pre-Law Work .615 152 Junior Tear •642 152 Social Science .462 152 Physical Science 561* .579 Total Pre-Law Work 361* .554 Junior Tear 83** .452 Total Pre-Law Work A supplementary study was mad© of these two indices for 361 students regardless of the institution in'which they had taken their pre-low work. **A supplementary study was made of this index for 83 students who had taken all their pre-law work at Institution© other than the University of Iowa.

-50Inspeetion of liable XXXI reveals that a moderate correlation of *47 was found between the composite scores on tlis Iowa qualifying Examination and the criterion of success in first year law for the 152 students who had received all their pre-law training at the University of Iowa. A multiple correlation of only *50 was obtained between the criterion and an optimum combination of the scores on the four sub-tests of the Qualifying Examination for this group* Of the indices studied for the above criterion group* the total pre-law grade point average appears to constitute the most valid single index of success in first year law* correlating .67 with the criterion. However* the data presented in Table XIV indicate that con­ siderable caution must be observed in using this index as the sole basis for the prognosis of individual scholastic success in the College of Law of the University of Iowa, m m when the counsel©© has taken all his undergraduate work at the University of Iowa. TABLE XIV Belationstiip between Total Pre-Law Grad© Point Averages and Bank in First Year Law Class Total 'dferiilSiir"^ ~".. '1 Ranic In^Flrst fear'Law CIs m w w "~ Point Average* Highest 25# Second 25# Third ZS% Lowest d Highest 2 5 g (3.87-4 2 29 ■i r ii Second 25# (3.46-2 5 a 16 6 16 Third 25# (2.32-2.45) 4 12 17 Lowest £5% (1.55-2.31)______5_______________ 9 __ _______________ 9 i I&Sed on 152 stSsnte who took all their pre-law work at the University of Iowa. **Baaed on 561 students who completed first year of law at the University of Iowa.

A multiple correlation of only .66 was obtained between the criterion and an optimum combination of total pre-law grade point averages and composite scores on the Qualifying Examination for this group. Apparently addition of this latter index adds little to the predictive value of total pre-law grades. Since it was found that* over the period of the study* students entering the University of Iowa College of Law had completed all or part of their undergraduate training at 85 different Institutions* supple­ mentary studies were made of available predictive indices for two different groups.

The first of these studies* based on the undergraduate

transcripts of 961 students regardless of the institution in which they had taken their pre-law work* yielded a correlation of ,58 between the criterion of success in first year law and total pre-law grade point averages and a correlation of ,55 between the same criterion and junior year pre-law grade point averages# A second supplementary study* based on the undergraduate transcripts of 83 students who had completed all their pre-law work at institutions other than the Univer­ sity of Iowa, yielded a correlation of only .45 between total pre-law grade point averages and the criterion of first year law school performance.

It would appear* therefore* that total undergraduate

grade point averages do not constitute a very effective index of scholastic success in law for students wiio enter the College of Law of the University of Iowa from other undergraduate institutions. In order to evaluate the possible efficacy of requiring a bachelor*s degree as one of the criteria for admission to the College of Law of the University of Iowa* the first year law grades of Z1Z students who had entered the law school prior to obtaining their

-52bachelors9 degrees were compared with the corresponding grades for 149 students who had received their degrees before entering law school, A critical ratio of 2.13* significant at approximately the Z percent level of confidence* was found between the means of the linear criterion scores for the two groups* indicating that the former group of students was actually superior in first year law performance to the group who had received their bachelors9 degrees before entering law school, This finding has been confirmed by similar studies in several other schools of law* A further study of these

twogroups revealed that theformer

group was slightly* although not significantly* superior to the latter group with respect to total pre-law grad© point averages. Apparently selective factors such as motivation* chronological age and continuity of college attendance* as well as

sciiolastic aptitude, must beinvoked

to account for the superiority of

thestudents who entered lawschool

after only three year# of pre-law preparation#

CHAFfRR IV SUMMARY A W CONCLUSION The objective of the present investigation was to determine the validity of certain indices for the prediction of scholastic success in first year law, The study involved (1) the construction* preliminary validation* and preparation of a tentative revision of a test designed to measure certain intellectual characteristics considered most essential to successful law school performance* and (2) a statistical evaluation of the validity of pre-law grade point averages and scores on the Iowa Qualifying Bxaminatlon as predictive indices of scholastic success in the College of Law of the University of Iowa, An experimental test battery comprising eight sub-tests was constructed* with the assistance of members of the faculty of the College of Law* and administered to 250 freshman students in eight different schools of law in the fall of 1941, A study of the internal consistency of the 455 items Included in the total experimental battery revealed that 94 items wore defective and should be replaced in future editions of the test. An index of difficulty was computed for each test item.

The relia­

bilities of the sub-tests* as estimated by the method suggested by Kuder and Richardson* ranged from ,75 to ,94* while the reliability of the total test was ,97, Correlations between total scores on the experimental battery and measures of first semester law school achievement were com­ puted for 29 cases in the University of Indiana* 42 cases In the Univer­ sity of Iowa* and 39 cases in the University of Pittsburgh.

The coef­

ficients of validity obtained were *42, ,67, and ,77, respectively. At the end of the 1941-42 academic year correlations between total test

-54scores and measures of first year law school performance were computed for 12 cases in the University of Cincinnati, 29 cases In the University of Indiana, 42 cases in the University of Iowa, 40 cases in Ohio state University, and 28 cases in the University of Pittsburgh* The obtained coefficients were *64, #48, ,71, *69, and ,76, respectively, Ihen the criterion groups from Indiana, Iowa, and Pittsburgh were combined into a single population, statistically significant cor­ relations, ranging from ,86 to ,57, were obtained between scores on individual sub-tests of the experimental battery and the criterion measures of first semester law school achievement for the composite group. Application of the Iberry-Doolittl© Test Selection Method yielded a maximum multiple correlation of ,67 between the criterion measures and an optimally weighted combination of the scores on three of the sub-tests of the experimental battery for this combined group. Since the criterion groups available were too small for satis­ factory reliability, validity coefficient® obtained in this preliminary study must be considered only of suggestive value. The presentation of norms and final reliability coefficients, together with more adequate data on validity, must await the preparation of a final revised edition of the test based on further experimentation Involving larger crite­ rion groups in individual colleges of law* In a supplementary study of 152 students who had taken all their pre-law work at the University of Iowa, a correlation of ,67 was found between total pre-law grade point averages and measures of first year law school achievement in the College of Law of the University of Iowa,

junior year pre-law grade point averages yielded a correlation

of ,62, social sciences a correlation of .64, physical sciences ,46,

while sub-test sad composite scores on the Iowa Qualifying Examination gave correlations with the criterion ranging from *54 to .47. For a group of S61 students, 209 of whom had taken part or all of their pre-law work at institutions other than the University of Iowa, the correlations between the criterion and total and junior year pre-law grade point aver­ ages were *58 and ,55, respectively.

For a third group of 33 students

who had taken all their pre-law work at institutions other than Iowa, a correlation of only ,45 was found between measures of first year law school performance and total pre-law grade point averages, A comparison of the first year law school achievement of 149 students who had received their bachelors9 degrees before entering law school with the achievement of 212 students who entered law school after oi&y three years of pre-law training revealed that the latter group was significantly superior to the former in first year law studies at the University of Iowa, Mo statistically significant differ­ ence was found between the total pre-law grades of these two groups. On the basis of the findings of the present study, the follow­ ing conclusions seem justifiedt 1. The experimental edition of the Iowa Legal Aptitude Test appear® to show considerable promise as a predictive index of scholastic success In law for populations similar to those included in this preliminary study. Further experimentation with this teat, involving larger criter­ ion groups and utilising more rigorous statistical techniques, should eventually result in a much shorter and more valid final edition. 2. Of the predictive Indices, obiter than the legal aptitude test, studied in the present investigation, total pre-law grade point averages appear to constitute the best single index of success in first year law

—66— for students entering the College of Law of the University of Iowa from the undergraduate division of this institution.

The validity of this

index is considerably higher for students who have taken all their pre­ law training at the university of Iowa than for students who have taken part of their undergraduate training elsewhere. For students who have taken all their pre-law work at other undergraduate institutions, the predictive value of pre-law grades alone is too low to be of much value for individual prediction* 3. Composite and sub-test scores on the Iowa Qualifying Examina­ tion do not seem to be sufficiently valid indices of scholastic success in first year law to be very useful for purposes of individual prediction at the University of Iowa. Combination of these indices with total pre­ law grade point averages by the method of multiple correlation does not materially Increase the predictive efficiency of this latter index. 4.

m a comparative study of the relative scholastic success in

law of students who entered the College of Law of the University of Iowa after only three years of undergraduate preparation and students who received their bachelors* degrees prior to entrance, no evidence was found to indicate the desirability of requiring college graduation as a prerequisite for admission to this college of law. 5. Counselors at the University of Iowa must take Into considera­ tion factors other than the Qualifying Examination scores, pre-law grade point averages, and legal aptitude test scores in appraising the capacity of individual students for success in law school. Somewhat inferior intellectual capacity, as indicated by some or all of these indices, may occasionally bo compensated by superior motivation, interest, health and other relatively nonintellectual factors not readily quantifiable

-57at the present time* Conversely, students possessing superior intellec­ tual capacity for the study of law may* due to the lack of certain of these essential xumlntelleciual characteristics* fail to attain scholas­ tic success in law commensurate with their intellectual potentialities. 6. Improvement of our ability to predict scholastic success in law will probably result from experimentation with optimal combinations of score® on improved tests of legal aptitude* pre-law grade point averages and, possibly* objective measures of less Intellectual char­ acteristics a® yet not adequately subjected to quantification. Of these latter, such factors a© interests, personality, perseverance, health, and personal history data in general are in need of further investigation In connection with this problem. Further analysis of the Intellectual functions required in legal studies and the development of more specific test® for* their measurement are needed.

—58—

BIBLIOGRAPHY X. Bingham, W. V# Aptitude® and Aptitude Testing. Hew Yorks Harper. 1957, pp. 177-185. 2. Cleeton, 0. 0. The optima difficulty of group teat elements, i* 1 W . L0, 527-540. 5. Crawford, A. B. The legal aptitude experiment at Yale. Amer. how Sch. Rev.. 1952, 7, 530-533. 4. Crawford, A. B., and Gorham, T. J. The Yale Legal Aptitude Test. Yale Law £ „ 1940, 49, 1257-1249. 5. Eagleton, W. L* Admission requirements for the law school and the bar. Aaaer. Law Sch. Rev,, 1982, 7* 521-529. 6. Ferson, H. L. Law aptitude exarsinatioris. Amer* Law v Sch, Kev., 1925, 5, 565-565. 7* Garrett, H* B* statistics in Psychology and Education, Mew Yorks Longmans, Green and Co., 1958, pp. 229-280. 8. G&udet, F* J., and Marryott, F. J* Predictive value of the FersonStoddard Law Aptitude Examination. Amgr. Law.Sch. Rev.. 1950* 7, 27-52. * ~ 9* Gulliver, A. G. Hie us© of a legal aptitude test in the selection of law school students* Arner. Law Sch. Rev., 1940, 9, 560-568. 10. Harrell, T. W. Predicting success of law school students* Amer. Law Sch. Rev*, 1989, 9, 290-295. XX. Burst, P. Item analysis by means of a maximising function. Psychometrlka» 1936, 1, 220-244. 12. Hull, C. L. Aptitude Testing. Hew York* World Book Co., 1928, pp. s5s£SS5T X5. Husband, H. W. Prediction of law school success. Wis. Law Rev., 1939, 14, 285-294. 14. Jacobs, A. C. Comments on Bean Gulliver1s paper (from a talk before the 37th Annual meeting of the Assoc, of Aaer. Law Schools). Aroer. Law Sch. Rev., 1940, 9, 665-667. 15. Kandel, I. L. Professional Aptitude Tests in Medicine, Law and ifri/d,neerlng. Bureau of Publications, Teachers college, Columbia University, 1940, pp. 51-60.

-6916. Kidd* A. Um

Comments on Bean Gulliver*a paper(from a talk before

the 37th annual meeting of the Assoc, of Amor* Law Schools).

Amer. Law Sch. Rev.. 1940* 9* 663-664. 17* Kuder* 6. F.# and. Bich&r&son, If. W. The theory of the estimation of test reliability. Psychometrika« 1957* 2* 151-160. 18. Lindquist* E. F. Statistical Analysis in Educational Research. Hew York: Houghton Mifflin* 1940* pp. 211-2X4. 19* Prosser* W. L. Cocsnente on Bean Gulliver*s paper (from a talk before the 57th annual meeting of the Assoc, of Amer. law Schools). Asaer. Law Sch. Rev.. 1940* 9* 658-663. 20. IHker* B. L.* and. Gaudet* F. J. The use of some tests In the prediction of legal aptitude. J. appl. Psychol.. 1941, 25* 5X3-522. 21. Seashore, C. E. Placement Examinations. Sch. & See.. 1824* 20* 575-578. 22. Stead, W. H», and Shartle, C. L. Occupational Counseling Techniques. Hew Torks American Bock Co.* 1940, pp. 245-250* Appendix ?. 23.

Stoddard, 0. 0. person and Stoddard Law Aptitude Examination preliminary report. Amer. Law Sch. Rev., 1927, 8, 78-81.

24. Syraonds, P. M. Choice of items for a test on the basis of dil'ficuXty. J..educ. Psychol., 1929* 20, 481-493. 25.

Thurstons* T. 0* Th© difficulty of a test and its diagnostic value. J. educ. Psychol.. 1932* 25* 335-343.

28. Wltham, H. B. Legal aptitude tests. 448—453.

III. Law Rev., 1930* 25,

27. Wood* Ben D, The measurement of law school work. Anor. I^aw Sch. Bev.. 1925, 5, 358-564.

—00m

APPENDIX A

-61-

3ggggS8ggg8g$g§3SS£®®® m

m

U

U

CO

% ■*

'““ s ^ a s s a s s s a ^ a

OOHOrtOO fr*

*0 l i s £ i 4

Hr4©8H«MWS^05W|g|ji^Jgggg€»«S>000 ■>MS IS O

m 1

—

■T-H 'iii

such services;

but is an action to recover specifically the amount of this

reward, $500. .There is no evidence introduced in the Court below to show what l------ ------— — — -— ----28 — the value of the services was, and.the record does not distinctly show what ------------------ „ 1 1--— 29 -----services were performed. The Court having erred in failing to charge as requested, and in charging the jury as above set out, we consider it unnecessary to say more about the case; and we therefore reverse the judgment. ---- - 3 0 ---------------- 1 Judgment reversed.

-31-

-119PART 6-A. DIRECTIONS: Examine each statement below and decide whether it is true or false, If it is true, circle the T to the left of the item; if it is false, circle the F to the left of the item. T

F

1. This is the opinion of the court that first tried the case.

T

F

2. The conviction of the woman was set aside in this action.

T

F

3* McMichael and Owens both acted in response to the offer.

T

F

4* Plaintiff finally recovered judgment according to this case.

T

F

5» The court here quoted reached its final decision because the offer had been withdrawn.

T

F

6 ., The judge in the court below gave an erroneous charge.

T

F

7« An offer may be made in a newspaper.

T

F

8 . The jury in the Biggers v. Owens case found that the woman

poisoned the meal. T F

An offer may be withdrawn any time before it is accepted.

T

F

10. Plaintiffs had not complied with the terms of the offer before its withdrawal.

T

F

11. Justice Blandford charged the jury.

T

F

12. McMichael recovered in this action the value of his services.

T

F

13. The court below charged the jury that the withdrawal of the offer was inoperative*

T

F

14* The arrest of the woman constituted an acceptance of the offer.

T

F 15. The judge in the court below held that the offer had not been withdrawn.

T

F

16. An offeror may specify the conditions upon which he will be contractually bound.

T

F

17. Pearce did not renew the original offer to McMichael.

T

F

18. A verdict of the jury does not constitute a judgment of the court.

T

F

19. The discharge of the woman by the justice of the peace precluded the possibility of the defendants being liable.

T

F

20. The public may accept an offer. CONTINUE TO NEXT PAGE -32-

-120-

PART 6-B. DIRECTIONS: Below is a hypothetical case similar to Biggers v. Owens, Indicate below each bracketed word ©r phrase the number of its analogue (i»e., similar part) in Biggers v. Owens. The first bracket is already correctly filled out. A “lO” is placed in the first bracket because the men listed in bracket 10 of Part 6 correspond to A in Part 6—B. A

said to B

Miop'-C

ffI will pay you Five Dollars if you will climb to the top

)^L( )-“----( )---,L— ( )-- ^

of that greased pole." --------

--- J

( )---

B proceeded to climb the pole. When B was two—thirds L------------(

)— „

—

of the way up A said to B "I revoke my offer to pay you.” B climbed to the top i-------- — , — _( > ----------,------ j i ------- .( ) ----of the pole.

B then sued A in the district court, to recover the Five Dollars.

------------- 1 L--- (

) ---- 1