We conduct a proper test of the claim that people are overconfident, in the sense that they believe that they are better than others. The results of the experiment we present do not allow us to reject the hypotheses that the data has been generated by perfectly rational, unbiased, and...

Many disasters are foreshadowed by insufficient preventative care. In this paper, we argue that there is a true problem of prevention, in that insufficient care is often the result of rational calculations on the part of agents. We identify three factors that lead to dubious efforts in care....

Numerous experiments demonstrate attitude polarization. For instance, Lord, Ross & Lepper presented subjects with the same mixed evidence on the deterrent effect of the death penalty. Both believers and skeptics of its deterrent effect became more convinced of their views; that is, the...

Many studies have shown that people display an apparent overconfidence. In particular, it is common for a majority of people to describe themselves as better than average. The literature takes for granted that this better-than-average effect is problematic. We argue, however, that, even...

Incentive compatible mechanisms for eliciting beliefs typically presume that money is the only argument in people's utility functions. However, subjects may also have non-monetary objectives that confound the mechanisms. In particular, psychologists have argued that people favour bets where...

In this paper we conduct two proper tests of overconfidence. We reject the hypothesis "the data cannot be generated by a rational model" in both experiments.

We conduct two experiements of the claim that people are overconfident. We develop new tests of overplacement which are based on a formal Bayesian model. Our two experiments, on easy quizzes, find overplacement. More precisely, we find apparently overconfident data that cannot be accounted for...

Many studies have shown that people display an apparent overconfidence. In particular, it is common for a majority of people to describe themselves as better-than-average. The literature takes for granted that this better-than-average is problematic. We argue, however, that, even accepting these...

Numerous experiments have demonstrated the possibility of attitude polarization. For instance, Lord, Ross & Lepper (1979) partitioned subjects into two groups, according to whether or not they believed the death penalty had a deterrent effect, and presented them with a set of studies on the...

Many studies have shown that people display an apparent overconfidence. In particular, it is common for a majority of people to describe themselves as better-than-average. The literature takes for granted that this better-than-average effect is problematic. We argue, however, that, even...