About the Army Beta
The Beta was created in 1917 alongside the Alpha by the same Yerkes committee. The Army discovered early in WWI that a large fraction of draftees - both recent immigrants and native-born Americans with limited schooling - could not read instructions on the Alpha. Two solutions were tried: individual examination (too slow for millions of recruits), and a fully non-verbal group test. The Beta was the second solution.
Every Beta subtest is administered with gestures and pantomime. The examiner demonstrates the task on a blackboard or chart; the recruit copies the procedure on the printed test booklet. No spoken or written language is required. The seven subtests were designed to tap different aspects of non-verbal reasoning - visual scanning, spatial relations, pattern recognition, motor speed, attention to detail.
The Beta survived in adapted form for decades. The Digit-Symbol Substitution subtest is essentially unchanged in the Wechsler Adult Intelligence Scale (WAIS) today. Picture Completion survives as a WAIS subtest. Cube Counting ancestrally relates to modern spatial-reasoning tests. The maze format is still used in clinical neuropsychology.
The seven subtests
How the Beta connects to modern IQ tests
The Beta was the most successful non-verbal cognitive battery of its era and directly influenced every modern non-verbal intelligence test:
- Performance subscales of the Wechsler tests (WAIS-IV Perceptual Reasoning, WISC-V Visual Spatial Index) descend from the Beta's design philosophy.
- Digit-Symbol Coding (WAIS-IV) is the Beta Test 4 with cosmetic changes.
- Picture Completion (WAIS-IV until 2008) was the Beta Test 6 with updated images.
- Block Design (WAIS-IV) descends from the Kohs Block Design (1923), which in turn was influenced by the Beta's spatial-construction items.
- Raven's Progressive Matrices (1938), though developed independently in the UK, drew on the same idea: that visual pattern reasoning could be measured without language.
The Army Beta's lasting contribution was demonstrating that a meaningful intelligence score could be obtained from people who shared no language with the examiner. That premise is now uncontroversial; in 1917 it was a major theoretical claim.
Source and verification
All test materials and answer keys on this page are transcribed from:
Yoakum, C. S. & Yerkes, R. M. (1920). Army Mental Tests. New York: Henry Holt and Company. Published by direction of the War Department. Beta materials reproduced on pages 277-283.
The full book is in the public domain in the United States: archive.org/details/armymentaltests00yoak. Note that the Yoakum & Yerkes volume reproduces the Beta with the correct answers marked directly on the page (mazes show the path, digit-symbol shows the filled symbols, etc.). The "keyed" version is what you see in our interactive subtests.
Want a modern IQ score?
The Army Beta is a historical artifact. For a contemporary IQ score with modern norms, take our full modern test.
Take the Modern IQ Test