5a. Choose between getting $900 for sure or a 90 percent chance of getting $1,000.
A. Getting $900
B. 90 percent chance of getting $1,000
5b. Choose between losing $900 for sure or a 90 percent chance of losing $1,000.
A. Losing $900
B. 90 percent chance of losing $1,000
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The results of this simple problem set, for which most participants answer A and then B, were used to develop the thesis that would make Kahneman and Tversky famous: prospect theory. In a 1979 paper, they documented a peculiar behavioral tendency: when people faced a gain, they became risk averse; when they faced a loss, they became risk seeking. As a result of their discovery, Kahneman and Tversky debunked Bernoulli’s utility theory, a cornerstone of economic thought since the 18th century. (Bernoulli first proponed that a person’s willingness to gamble a certain amount of money was a product of how that amount related to his overall wealth—that is, $1 million means more to a millionaire than it does to a billionaire.)
Along with playing a large role in Kahneman’s being awarded the Nobel Prize in 2002, the theory also spawned a new academic pursuit, the field of behavioral economics. Prospect theory, Michael Lewis writes, explains “why people are less likely to sell their houses and their stock portfolios in falling markets; why, most sensationally, professional golfers become better putters when they’re trying to save par (avoid losing a stroke) than when they’re trying to make a birdie (and gain a stroke).”
via The Quiz Daniel Kahneman Wants You to Fail | Business | Vanity Fair.