Amos_Tversky

Amos Tversky

Amos Nathan Tversky, PhD (עמוס טברסקי; March 16, 1937 - June 2, 1996) was a cognitive and mathematical psychologist, and 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. Later, he and Kahneman originated prospect theory to explain irrational human economic choices. Daniel Kahneman's autobiography for the Nobel Prize webpage contains a rich account of Tversky's personal and professional qualities and a eulogy, starting with the section "Collaboration with Amos Tversky." Daniel Kahneman received the Nobel Prize for the work he did in collaboration with Amos Tversky, who would have no doubt shared in the prize had he been alive.

Tversky received his doctorate from the University of Michigan in 1964, and later taught at the Hebrew University in Jerusalem, before moving to Stanford University. In 1984 he was a recipient of the MacArthur Fellowship. Amos Tversky was married to Barbara Tversky, then a professor in the human development department at Teachers College, Columbia University. He died of a metastatic melanoma in his home.

He also collaborated with Thomas Gilovich, Paul Slovic and Richard Thaler in several key papers.

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.