Mark R. Lepper (born December 5, 1944) is the Albert Ray Lang Professor of psychology at Stanford University, and a leading theorist in

social psychology Social psychology is the scientific study of how thoughts, feelings, and behaviors are influenced by the real or imagined presence of other people or by social norms. Social psychologists typically explain human behavior as a result of the re ...

. He is particularly known for his research on

attribution theory Attribution is a term used in psychology which deals with how individuals perceive the causes of everyday experience, as being either external or internal. Models to explain this process are called attribution theory. Psychological research into a ...

and confirmation bias, and for his collaborations with Lee Ross.

Life

Lepper is primarily responsible for the elucidation of the overjustification effect, alongside

Richard Nisbett __NOTOC__ Richard Eugene Nisbett (born June 1, 1941) is an American social psychologist and writer. He is the Theodore M. Newcomb Distinguished Professor of social psychology and co-director of the Culture and Cognition program at the University ...

. With frequent collaborator Lee Ross, and Robert Vallone, he authored the first study to identify the

hostile media effect The hostile media effect, originally deemed the hostile media phenomenon and sometimes called hostile media perception, is a perceptual theory of mass communication that refers to the tendency for individuals with a strong preexisting attitude on a ...

. With Ross and Charles Lord he also authored an important study on attitude change and what is now called disconfirmation bias. With Lord he later theorized attitude representation theory. He has also worked with

Thomas Gilovich Thomas Dashiff Gilovich (born January 16, 1954) an American psychologist who is the Irene Blecker Rosenfeld Professor of Psychology at Cornell University. He has conducted research in social psychology, decision making, behavioral economics, and ...

and Merrill Carlsmith. Lepper attended Stanford University as an undergraduate, earning a

B.A. Bachelor of arts (BA or AB; from the Latin ', ', or ') is a bachelor's degree awarded for an undergraduate program in the arts, or, in some cases, other disciplines. A Bachelor of Arts degree course is generally completed in three or four years ...

with great distinction in psychology in 1966. He subsequently earned a

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

in Social and Developmental Psychology at Yale University in 1970, returning to Stanford in 1971 as an assistant professor. Lepper became a full professor of psychology and, by courtesy, of education in 1982, and has since served as chairman of the department of psychology between 1990 and 1994, and again after 2000. He is a fellow of the

American Psychological Association The American Psychological Association (APA) is the largest scientific and professional organization of psychologists in the United States, with over 133,000 members, including scientists, educators, clinicians, consultants, and students. It has ...

and a charter fellow of the American Psychological Society.

External links

Official site
{{DEFAULTSORT:Lepper, Mark 1944 births Living people Social psychologists Stanford University Department of Psychology faculty Fellows of the American Psychological Association