Z:gnu-www-ja-frank--387eed-Clearly, our evidence for the/en

Clearly, our evidence for the existence of a difference between the behavior of economists and noneconomists is more compelling than our evidence for the causal role of economics training in creating that difference. But there is additional indirect evidence for such a role. One of the clearest patterns to emerge in several decades of experimental research on the prisoner's dilemma is that the behavior of any given player is strongly influenced by that player's prediction about what his partner will do. In experiments involving noneconomists, people who expect their partners to cooperate usually cooperate themselves, and those who expect their partners to defect almost always defect. In our experiments, economists were 42 percent more likely than noneconomists to predict that their partners would defect. It would be remarkable indeed if none of this difference in outlook were the result of repeated exposure to a behavioral model whose unequivocal prediction is that people will defect whenever self-interest dictates.