Find a chapter
Every chapter of the three parts, and the reproduced materials in Part I, chapter 5, with the starting page from the volume's own table of contents [1]. Type a word or pick one.
I · 1Preofficial period of preparation for national servicep. 7
I · 2Official military trial of psychological examiningp. 11
I · 3Period of extension of examiningp. 27
I · 4General summaryp. 91
I · 5Provision of materials for psychological examiningp. 120
I.5 · §1Examiner's Guide, first revisionp. 123
I.5 · §2Instructions for scoring and combining tests of individual examination seriesp. 149
I.5 · §3Examiner's Guide, second revisionp. 153
I.5 · §4Examiner's Guide for Students' Army Training Corpsp. 200
I.5 · §5Examinations a and bp. 201
I.5 · §6Examination alphap. 219
I.5 · §7Examination beta, preliminary formp. 235
I.5 · §8Examination beta, form 0p. 250
I.5 · §9Stencils for scoring group examinationsp. 259
I.5 · §10Individual examinationsp. 259
I.5 · §11Literacy testsp. 279
I.5 · §12Report blanksp. 286
II · 1Work of the committee at Vineland, N. J.p. 299
II · 2Unofficial trial of methodsp. 313
II · 3Acceptance of methods by the War Department and early modifications resulting from official usep. 325
II · 4Revision of group examination ap. 327
II · 5Methods of segregationp. 347
II · 6Development of a substitute group test for illiterates and foreignersp. 363
II · 7Data obtained through more extensive camp trial of examination beta and resulting modificationsp. 379
II · 8Revision of methods of individual examinationp. 397
II · 9Effect of doubling the time limits in the alpha and beta examinationsp. 415
II · 10The assignment of letter ratingsp. 421
II · 11Performance in intelligence examinations as related to officers' estimates of intelligencep. 425
II · 12Performance in intelligence examinations as related to military efficiencyp. 453
II · 13Conditions of examining and procedure adopted during the initial experimentp. 469
II · 14Summary of data concerning groups examinedp. 487
II · 15Additional statistics on examination ap. 533
III · 1Sampling of intelligence records and mode of analysisp. 553
III · 2A general method of statistical interpretation of the principal samplep. 573
III · 3Comparison of forms of examination alphap. 659
III · 4Camp differences in intelligence ratingsp. 665
III · 5Intelligence ratings by statesp. 681
III · 6Relation of intelligence ratings to nativityp. 693
III · 7Relation of intelligence ratings to length of residence in United Statesp. 701
III · 8Intelligence of the negrop. 705
III · 9Literacyp. 743
III · 10Statistics on education and its relation to intelligence examinationsp. 747
III · 11Intelligence of the draft in relation to fitness for military servicep. 785
III · 12Disciplinary casesp. 799
III · 13Influence of certain physical conditions on the intelligence scorep. 809
III · 14Relation of intelligence ratings to agep. 813
III · 15Intelligence ratings of occupational groupsp. 819
III · 16Relation of ratings to arm of the servicep. 839
III · 17Relation of rank to intelligencep. 853
III · 18Officers' training camps and noncommissioned officers' schoolsp. 861
III · 19Data from colleges and the Students' Army Training Corpsp. 869
III · 20Distribution of scores on the tests in examinations alpha and betap. 873
IndexSubject indexp. 877
53 of 53 entries shown · Titles as printed, including period terms. Page numbers from the scanned contents; a few are hard to read in the scan.
Who prepared it
The introduction says the work was so cooperative that "no formal ascription of credit is possible". Yerkes still names three staff officers who made completion possible [1]. He signed the general introduction on 17 May 1920, as a lieutenant colonel.
Robert M. YerkesEDITOR · CHIEF OF THE DIVISION
Chief of the Division of Psychology in the Surgeon General's Office. Signed the general introduction on 17 May 1920, and Part I's on 15 May.Lewis M. TermanMAJOR
Responsible for preparing the account of methods.Edwin G. BoringCAPTAIN
Directed the analysis of results and helped edit Part I. Took over editorial responsibility once Yerkes had left the service.Harold C. BinghamMAJOR
As Chief of the Section of Psychology, read the proofs and prepared the index, which Yerkes calls a "laborious and thankless task".The report's own warnings
After the armistice, staff were being discharged faster than the data could be analysed. The general introduction is frank about what that cost [1].
"It was necessary to choose between the preparation of a report which contained a maximum of material and one which expressed a maximum of precision. The decision rested with the first alternative."General introduction. Many of the volume's "obvious defects", it says, follow from this choice.
"In Part III the results of examining are presented in summary fashion, and … wholly inadequately."The editors' own description of the results section, which became the most quoted part.
"The three parts of the volume are interdependent. No one of them can be used satisfactorily … apart from the others."A warning against reading the results without the history and methods.
PART III, CHAPTERS 5–8The chapters that travelled furthestRatings by state, by nativity, by length of residence in the United States, and by race. The Army segregated its records by race, and the volume reports them that way.
Ch. 5"Intelligence ratings by states"p. 681
Ch. 6"Relation of intelligence ratings to nativity"p. 693
Ch. 7"Relation of intelligence ratings to length of residence in United States"p. 701
Ch. 8"Intelligence of the negro"p. 705
References
- [1]Yerkes, R. M. (Ed.). (1921). Psychological examining in the United States Army. Memoirs of the National Academy of Sciences, Vol. XV. Washington: Government Printing Office. Internet Archive (University of Toronto copy).archive.org
- [2]Yerkes' Army Intelligence Tests (supporting material, quoting S. J. Gould, The Mismeasure of Man). New Learning Online.newlearningonline.com
HOW TO CITE THIS PAGE
What's Your IQ. (2026). Psychological Examining in the United States Army (Yerkes, 1921). In Historical IQ Tests Archive. Retrieved October 1, 2026, from /en/historical-iq-tests/yerkes-1921-memoirs
EDITORIAL RECORD
First published2026
Last reviewed1 October 2026
SourcesThe volume itself (front matter, contents, introductions and Part I, chapter 1 read in full); one secondary account of its reception
CorrectionsRemoved from the previous version: "all five Alpha forms in full" with per-camp norms; "all 7 Beta subtests" (the plates show Beta blackboard demonstrations for tests 1–8); "factor analyses"; "norms on 1.7 million recruits"; "890 pages" as a headline (the subject index begins on p. 877); a PDF link to an unverified scan.
Open questionsExact page count of the bound volume; the overall total examined as stated in Part I, chapter 4
Canonical URLwhats-your-iq.com/en/historical-iq-tests/yerkes-1921-memoirs
Documented in this volume
Part I, ch. 5 §71917
The Army Alpha Test
The volume reproduces "Examination alpha" among the printed materials, from p. 219. Part III, chapter 3, compares its forms.
InteractiveTake it →
Part II, ch. 6–71918
The Army Beta Test
Two Part II chapters cover the "substitute group test for illiterates and foreigners" and its camp trials. Plates 15–16 show the blackboard demonstrations.
InteractiveTake it →
Part II, ch. 81918
Army Individual Examination
The revision of individual examining has its own chapter. The plates show the Stanford-Binet and the ten-test performance scale in use.
InteractiveTake it →
The editor's earlier scale1915
Yerkes-Bridges Point Scale
Yerkes's pre-war point scale was one of the individual methods the Army drew on. It shows the approach he brought to the Vineland committee.
InteractiveTake it →
What the authors did next1920
National Intelligence Tests
While the report was being finished, Yerkes was chairing the committee that adapted Army methods for schools. Terman and Whipple joined him there too.
InteractiveTake it →
The next war1942
Army General Classification Test
The WWII Army built a new classification test rather than reusing Alpha. This volume was the record of what the first attempt had done and found.
InteractiveTake it →
Part of the Historical IQ Tests Archive. Editorial content under CC BY-SA 4.0. The 1921 report is a US government publication in the public domain; read it on the Internet Archive.