Louis Leon Thurstone was a U.S. pioneer in the fields of psychometrics and psychophysics. He conceived the approach to measurement known as the law of comparative judgment, and is well known for his contributions to factor analysis. A Review of General Psychology survey, published in 2002, ranked Thurstone as the 88th most cited psychologist of the 20th century, tied with John Garcia, James J. Gibson, David Rumelhart, Margaret Floy Washburn, and Robert S. Woodworth.
Louis Leon Thurstone was born in Chicago, Illinois, to Swedish immigrant parents. Thurstone originally received a masters in mechanical engineering from Cornell University in 1912. Thurstone was offered a brief assistantship in the laboratory of Thomas Edison. In 1914, after two years as an instructor of geometry and drafting at the University of Minnesota, he enrolled as a graduate student in psychology at the University of Chicago . He later returned to the University of Chicago where he taught and conducted research. In 1952, he established the L. L. Thurstone Psychometric Laboratory at the University of North Carolina at Chapel Hill.
Source: Wikipedia