March 16, 1937|
Haifa, British Palestine (now Israel)
|Died||June 2, 1996
|Fields||Cognitive psychology, Behavioral economics|
|Institutions||Hebrew University, Stanford University|
|Alma mater||University of Michigan|
|Known for||Prospect theory|
Amos Nathan Tversky (Hebrew: עמוס טברסקי; March 16, 1937 – June 2, 1996) was a cognitive and mathematical psychologist, a pioneer of cognitive science, a longtime collaborator of Daniel Kahneman, and a key figure in the discovery of systematic human cognitive bias and handling of risk. Much of his early work concerned the foundations of measurement. He was co-author of a three-volume treatise, Foundations of Measurement (recently reprinted). His early work with Kahneman focused on the psychology of prediction and probability judgment. Amos Tversky and Daniel Kahneman worked together to develop prospect theory, which aims to explain irrational human economic choices and is considered one of the seminal works of behavioral economics. Six years after Tversky's death, Kahneman received the 2002 Nobel Prize in Economics for the work he did in collaboration with Amos Tversky. (The prize is not awarded posthumously.) Kahneman told The New York Times in an interview soon after receiving the honor: "I feel it is a joint prize. We were twinned for more than a decade." Tversky also collaborated with Thomas Gilovich, Itamar Simonson, Paul Slovic and Richard Thaler in several key papers.
Tversky was born in Haifa, British Palestine (now Israel). He served with distinction in Israel Defense Forces rising to a rank of captain and was decorated for bravery. He received his undergraduate education at Hebrew University of Jerusalem Israel, and his doctorate from the University of Michigan in Ann Arbor in 1964. He later taught at the Hebrew University, Israel before moving to Stanford University. In 1980 he became a fellow of the American Academy of Arts and Sciences . In 1984 he was a recipient of the MacArthur Fellowship, and in 1985 he was elected to the National Academy of Sciences . Amos Tversky was married to Barbara Tversky, now a professor in the human development department at Teachers College, Columbia University. Tversky, co-recipient with Daniel Kahneman, earned the 2003 University of Louisville Grawemeyer Award for Psychology. He died of a metastatic melanoma.
Comparative Ignorance 
Tversky and Fox (1995) addressed ambiguity aversion, the idea that people do not like ambiguous gambles or choices with ambiguity, with the comparative ignorance framework. Their idea was that people are only ambiguity averse when their attention is specifically brought to the ambiguity by comparing an ambiguous option to an unambiguous option. For instance, people are willing to bet more on choosing a correct colored ball from an urn containing equal proportions of black and red balls than an urn with unknown proportions of balls when evaluating both of these urns at the same time. However, when evaluating them separately, people are willing to bet approximately the same amount on either urn. Thus, when it is possible to compare the ambiguous gamble to an unambiguous gamble people are averse — but not when one is ignorant of this comparison.
Notable contributions 
- foundations of measurement
- anchoring and adjustment
- availability heuristic
- base rate fallacy
- conjunction fallacy
- behavioral finance
- clustering illusion
- loss aversion
- prospect theory
- cumulative prospect theory
- representativeness heuristic
- Tversky index
- support theory
- contrast model
- Altman, Daniel (10 October 2002). "A Nobel That Bridges Economics and Psychology". The New York Times. Retrieved 14 March 2009.
- Goode, Erica (5 November 2002). "A Conversation with Daniel Kahneman; On Profit, Loss and the Mysteries of the Mind". The New York Times. Retrieved 14 March 2009.
- Freeman, Karen (6 June 1996). "Amos Tversky, Expert on Decision Making, Is Dead at 59". The New York Times. Retrieved 14 March 2009.
- Fox, Craig R.; Amos Tversky (1995). "Ambiguity Aversion and Comparative Ignorance". Quarterly Journal of Economics 110 (3): 585–603. doi:10.2307/2946693. JSTOR 2946693.