Much of his early work concerned the foundations of measurement. He was co-author of a three-volume treatise, Foundations of Measurement. His early work with Daniel Kahneman focused on the psychology of prediction and probability judgment; later they 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 Memorial Prize in Economic Sciences for the work he did in collaboration with Amos Tversky.[1] (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."[2]
Tversky was born in Haifa, British Palestine (now Israel), as son of the Polish-born veterinarian Yosef Tversky and Lithuanian JewishJenia Tversky (née Ginzburg), a social worker who later became a member of the Knesset representing the Mapai (Workers' Party).[4] Tversky had one sister, Ruth, thirteen years his senior.
Tversky's mother has said he was self-taught in many areas, including mathematics.[5] In high school, Tversky took classes from literary critic Baruch Kurzweil, and befriended classmate Dahlia Ravikovich, who would become an award-winning poet.
During this time he was also a member and leader in Nahal, an Israel Defense Forces program that combined compulsory military service with the establishment of agricultural settlements.[6]
Tversky served with distinction in the Israel Defense Forces as a paratrooper, rising to the rank of captain and being decorated for bravery.[4] He parachuted in combat zones during the Suez Crisis in 1956, commanded an infantry unit during the Six-Day War in 1967, and served in a psychology field-unit during the Yom Kippur War in 1973.[6]
Academic career
Academic roles
After his doctorate, Tversky taught at Hebrew University. He then joined the faculty of Stanford University in 1978, where he spent the rest of his career.
Academic work
Work with Daniel Kahneman
Amos Tversky's most influential work was done with his longtime collaborator, Daniel Kahneman, in a partnership that began in the late 1960s. Their work explored the biases and failures in rationality continually exhibited in human decision-making.[6] Starting with their first paper together, "Belief in the Law of Small Numbers", Kahneman and Tversky laid out eleven "cognitive illusions" that affect human judgment, frequently using small-scale empirical experiments that demonstrate how subjects make irrational decisions under uncertain conditions. (They introduced the notion of cognitive bias in 1972.[7]) This work was highly influential in the field of economics, which had largely presumed rationality of all actors.[8]
According to Kahneman the collaboration 'tapered off' in the early 1980s, although they tried to revive it.[9] Factors included Tversky receiving most of the external credit for the output of the partnership, and a reduction in the generosity with which Tversky and Kahneman interacted with each other.[10]
Comparative ignorance
Tversky and Fox (1995)[11] 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.
Kahneman said that Tversky "had simply perfect taste in choosing problems, and he never wasted much time on anything that was not destined to matter. He also had an unfailing compass that always kept him going forward.[12]
Tversky's 1974 Science article with Kahneman on cognitive illusions triggered a "cascade of related research," Science News wrote in a 1994 article tracing the recent history of research on reasoning. Decision theorists in economics, business, philosophy and medicine as well as psychologists cited their work.[13]
After Tversky's death, Kahneman was awarded the 2002 Nobel Memorial Prize in Economic Sciences for the work he did in collaboration with Tversky. Nobel prizes are not awarded posthumously.[1]
Personality and characteristics
Kahneman has said "Amos was the freest person I have known, and he was able to be free because he was also one of the most disciplined."[16]
Persi Diaconis, a professor of mathematics at Stanford, has said "You were happy being in his presence. There was a light shining out of him."[13]
Gerhard Casper, President of Stanford University, said Tversky "maintained the highest standards of professional ethics", and "His dedication to Stanford and its institutions of faculty governance was exemplary."[13]
Whilst being very collaborative, Tversky also had a lifelong habit of working alone at night while others slept.[17]
In intellectual debate Tversky "wanted to crush the opposition".[18][19]
Tversky believed that humans live under uncertainty, in a probabilistic universe.[20]
^ abPriceless: The Hidden Psychology of Value
By William Poundstone
^ abcdeLewis, Michael (2017). The Undoing Project. New York: W. W. Norton & Company. ISBN978-0-393-35610-6.
^Kahneman D, Frederick S (2002). "Representativeness Revisited: Attribute Substitution in Intuitive Judgment". In Gilovich T, Griffin DW, Kahneman D (eds.). Heuristics and Biases: The Psychology of Intuitive Judgment. Cambridge: Cambridge University Press. pp. 51–52. ISBN978-0-521-79679-8.
^Kahnemnan, quoted in Michael Lewis, "The Undoing Project: A Friendship that Changed the World". Penguin, 2016 (ISBN 9780141983035)
^Tversky..." didn't have Danny's feeling that we should all think together and work together. He thought "F*** You". Walter Mischel, quoted in Michael Lewis, "The Undoing Project: A Friendship that Changed the World". Penguin, 2016 (ISBN 9780141983035)
^"People live under uncertainty whether they like it or not..... Man is a deterministic device thrown into a probabilistic Universe. In this match, surprises are expected." Notes made by Tversky for a scientific paper. Michael Lewis. "The Undoing Project: A Friendship that Changed the World". Penguin, 2016 (ISBN 9780141983035).
