Cronbach, Lee J. (1916–2001)

Lee J. Cronbach, known widely as the creator of Cronbach's alpha, was a man whose deep interests in psychological testing and educational psychology combined as the focus of more than 50 years of research into measurement theory, program evaluation, and instruction.

Cronbach was born in Fresno, California, and came to the attention of Blanche Cummings, a follower of Lewis Terman, when his precociousness at the age of 4 made itself known as she overheard him calculating the price of potatoes at a grocery store. Ms. Cummings gave the Stanford-Binet to Cronbach in 1921 and ensured wide publicity of his score of 200. According to Cronbach, this number was inflated; however, his future eminence was not, as evidenced by his many lifetime contributions.

Because of his mother and Ms. Cummings, Cronbach's education began, not with kindergarten, but with the second grade. He graduated from high school at 14 and immediately went to college, graduating at age 18. Interestingly, Cronbach's first higher educational interests lay in chemistry and mathematics; had not a lack of funds kept him at Fresno State, he may never have discovered his passion for educational research. He went on to Berkeley for a master's in education, gaining his teaching credentials at the same time. Cronbach then taught high school (math and chemistry) while he finished an education doctorate at the University of Chicago, graduating in 1940. He married Helen Claresta Bower while at Chicago, and their five children arrived between 1941 and 1956.

While at the University of Chicago, he became a research assistant for Ralph Tyler in the Eight-Year Study, which looked into how high school curriculum affected students' success in both admission to and graduation from colleges and universities. On graduation, Cronbach worked as an associate professor at Washington State University, where he taught myriad psychology courses. Toward the end of World War II, he worked as a military psychologist at the Naval [Page 204]Sonar School in San Diego, California. Cronbach went back to the University of Chicago as an associate professor and then on to the University of Illinois as a full professor. In 1964, he landed in Palo Alto, California, where he taught, conducted research, and finally retired at Stanford University, gaining the prestigious Vida Jacks Professor of Education Emeritus honor (among many others) during his tenure.

Cronbach's most famous contributions to the area of tests and measurements were his efforts at strengthening tests and measures through a deeper understanding of what constituted measurement error; i.e., that error had many sources. This led to the 1951 paper “Coefficient Alpha and the Internal Structure of Tests.” The subsequent results of this work led to further research and ultimately a rewriting of generaliz-ability theory with Goldine Gleser. Referred to as G Theory, these results brought together mathematics and psychology as an aggregate structure within which error sources may be identified.