Louis Leon Thurstone

Born May 29, 1887, in Chicago; died Sept. 29, 1955, in Chapel Hill, N.C. American psychologist.

Thurstone graduated from Cornell University in 1912. He was a professor of psychology at the Carnegie Institute of Technology in 1915 and at the University of Chicago from 1924 to 1952. He was one of the first to use mathematical methods in psychology and sociology. His search for “the objective within the subjective” led Thurstone to the formulation in 1927 of his law (equation) of comparative judgment. According to this law, comparisons may be made—under certain assumptions—of the intensity not only of quantitative but also of qualitative stimuli. This equation is used in social psychology to evaluate judgments expressed by public opinion; it is also widely used in quantitative studies of ethnocentrism and in research on the psychology of consumer groups. The works of Thurstone and E. Bogardus in this field laid the foundations for experimental social psychology in the West.

Carrying on the work of C. Spearman, E. Thorndike, and J. Cattell in the field of factor analysis, Thurstone in the late 1930’s developed multiple-factor analysis, which is widely used in psychology, sociology, economics, and anthropology. A number of Thurstone’s works, and particularly those on methods of identifying gifted persons, have exerted considerable influence on psychological studies of creativity. Thurstone is best known for his work on the measurement of attitudes and decision-making processes and on ranking and scaling methods.