Overconfident: Do You Put Your Money on It?
实验发现，当任务从简单熟悉变为不熟悉时，人们的选择行为从过度自信转为信心不足，且在有金钱报酬时效应显著。
A group exhibits overconfidence if significantly more than half the group members declare to be better than the median in some characteristic. Overconfidence was found in verbal reports for a variety of characteristics and settings but was less often studied for choice behaviour. In an experiment we tested how perceived relative skill influences verbal and choice behaviour. Treatments varied task difficulty and payment. Choice behaviour changes from overconfidence to underconfidence when the task changes from easy and familiar to non-familiar. This effect is significant when monetary payments are at stake and weak when they are not. People may be overconfident in many different ways: they may overestimate their abilities; they may perceive themselves more favourably than others perceive them; or finally, they may perceive themselves more favourably than they perceive others. An important example of the latter bias is the observation that a majority of people estimates their skills or abilities to be better than the median. This is the meaning of overconfidence that we adopt here. Clearly a widespread overconfidence would have important consequences in economic behaviour. In fact, the literature in economics and finance on theories, models, implications and practical effects of