Publications

Prospect theory, first described in a 1979 paper by Daniel Kahneman and Amos Tversky, is widely viewed as the best available description of how people evaluate risk in experimental settings. While the theory contains many remarkable insights, it has proven challenging to apply these insights in economic settings, and it is only recently that there has been real progress in doing so. In this paper, after first reviewing prospect theory and the difficulties inherent in applying it, I discuss some of this recent work. It is too early to declare this research effort an unqualified success. But the rapid progress of the last decade makes me optimistic that at least some of the insights of prospect theory will eventually find a permanent and significant place in mainstream economic analysis.

Casino gambling is a hugely popular activity around the world, but there are still very few models of why people go to casinos or of how they behave when they get there. In this paper, we show that prospect theory can offer a surprisingly rich theory of gambling, one that captures many features of actual gambling behavior. First, we demonstrate that, for a wide range of parameter values, a prospect theory agent would be willing to gamble in a casino, even if the casino only offers bets with zero or negative expected value. Second, we show that prospect theory predicts a plausible time inconsistency: at the moment he enters a casino, a prospect theory agent plans to follow one particular gambling strategy; but after he enters, he wants to switch to a different strategy. The model therefore predicts heterogeneity in gambling behavior: how a gambler behaves depends on whether he is aware of the time-inconsistency; and, if he is aware of it, on whether he is able to commit, in advance, to his initial plan of action.