We introduce a game theory model of individual decisions to cooperate by contributing personal resources to group decisions versus by free-riding on the contributions of other members. In contrast to most public-goods games that assume group returns are linear in individual contributions, the...

When a person evaluates his or her confidence in a judgment, what is the effect of receiving more judgment-relevant information? We report three studies that show when judges receive more information, their confidence increases more than their accuracy, producing substantial confidence-accuracy...