John B. Carroll

John Bissell Carroll (June 5, 1916 – July 1, 2003) was an American psychologist known for his contributions to psychology, educational linguistics and psychometrics.

Early Years
Carroll was born in Hartford, Connecticut. Early in his life, Carroll became interested in music and language. His interest in language was further sparked by becoming friends with Benjamin Lee Whorf at the age of thirteen and discussing Whorf’s ideas about a close connection between culture and language. Carroll also helped to edit and publish Whorf’s Language, Thought and Reality in 1956.

Education
Carroll studied at Wesleyan University, majoring in Classics and graduating summa cum laude in 1937. He attended the University of Minnesota to earn a doctoral degree in Psychology. At the University of Minnesota, Carroll began studying under B. F. Skinner, but soon discovered that he was more interested in working with large numbers of subjects rather than Skinner’s individual subjects approach. Skinner directed Carroll to L. L. Thurstone at the University of Chicago, where he able to pursue his interest in psychometrics. During this time, he focused his studies on verbal aptitude and completed his dissertation, “A Factor Analysis of Verbal Abilities,” in 1941.

Career
After finishing his education, Carroll’s first position was at Mount Holyoke College (1940-42). Mary Searle, who received her B.A. in psychology from Mount Holyoke in 1941, married Carroll after graduation.

After Mount Holyoke, Carroll taught at Indiana University (1942-43), the University of Chicago (1943-44), Harvard Graduate School of Education, (Roy E. Larsen Professor of Education, 1949-67) and the University of North Carolina, (William R. Kenan, Jr., Professor of Psychology 1974-82, Director of L. L. Thurstone Psychometric Laboratory, 1974-79).

He was also a psychologist with the United States Navy, (1944-46), the Department of the Army, (1946-49) and the Educational Testing Service (1967-74).

Contributions
One of Carroll’s early projects in the 1950s involved developing a test of language aptitude (the Modern Language Aptitude Test (1953-58), or MLAT). The project grew out of the US Army’s need for a way to select people who could easily learn foreign languages so that the government could spend the time and funds on those who would benefit most from foreign language training. Initially, the government gave project funding to a professor at a university closer to the Defense Language School in Monterey, California, but his research was unsuccessful at providing a useful assessment tool. Carroll then received a grant for foreign language learning aptitude research through the Carnegie Corporation and worked with Stanley Sapon and the US Army-Air Force to develop the Modern Language Aptitude Test. The MLAT was published in 1959 by the Psychological Corporation and is still used today by many government organizations in the US and abroad to measure language learning aptitude and select candidates for language training programs.

In his paper “Fundamental considerations in testing for English language proficiency of foreign students,” published in 1961, Carroll challenged the language testing field’s reliance on discrete-point test design. Discrete-point testing is an analytical approach to language testing in which each test question is meant to measure one distinct content point. Carroll supported using an integrative testing design, in which each question requires the test-taker to use more than one skill or piece of knowledge at a time and may be a more natural representation of the test-taker’s knowledge of the language. Carroll’s paper influenced the design of the Test of English as a Foreign Language, or TOEFL, which combined both discrete-point and integrative methods for the assessment.

In 1962, Carroll presented his Model of School Learning. In the model, Carroll defined a hypothetical framework used to predict achievement in schools. The framework was made up of two kinds of variables: individual differences and instructional variables. Individual differences related to general intelligence, aptitudes and motivation while instructional variables related to instructional quality and duration. Still influential in achievement and evaluation thinking, his model was revisited in “The Carroll Model: A 25 Year Retrospective and Prospective View,” published by the Educational Researcher in 1989.

But the culmination of Carroll’s life’s work in psychology is his 800 page work, Human Cognitive Abilities: A survey of factor-analytic studies, published in 1993, in which Carroll proposes his psychological theory about three different levels of cognition, the Three Stratum Theory.

In 1994 he was one of 52 signatories on "Mainstream Science on Intelligence," an editorial written by Linda Gottfredson and published in the Wall Street Journal, which defended the findings on race and intelligence in The Bell Curve.

According to David Lubinski, a psychology researcher at Vanderbilt University, Carroll was known not only for his contributions to academia, but also his “profound intellectual gifts, curiosity, optimism, wit, and unfailing integrity and sincerity.”

Selected Publications
Selected from over 400 books and articles.


 * Carroll, J B 1956  Language, Thought, and Reality: Selected Writings of Benjamin Lee Whorf  M.I.T. Press, Boston.
 * Carroll, J B 1993  Human Cognitive Abilities  Cambridge University Press, Cambridge.
 * Carroll, J B, Davies, P, & Richman, B 1971  The American Heritage Word Frequency Book.  Houghton Mifflin, New York.
 * Carroll, J B, Sapon, S M 1959  Modern Language Aptitude Test The Psychological Corporation, San Antonio, Texas.
 * Carroll, J B, 1961  "Fundamental considerations in testing for English language proficiency of foreign students".  In Testing  Center for Applied Linguistics, Washington, DC.  Reprinted in Allen, H B & Campbell R N  1972  Teaching English as a Second Language: A Book of Readings  McGraw Hill, New York.
 * Carroll, John B. Human Cognitive Abilities: A survey of factor-analytic studies. Cambridge: Cambridge University Press, 1993.
 * “John B. Carroll.” Human Intelligence. 2003. Indiana University. 27 June, 2006. http://www.indiana.edu/~intell/carroll.html.