Several authors suggest that trust is an important determinant of cooperation between strangers in a society, and therefore of performance of social institutions. We argue that trust should be particularly important for the performance of large organizations. In a cross-section of countries,...

We evaluate Richard Posner's famous hypothesis that common law converges to efficient legal rules using a model of precedent setting by appellate judges. Following legal realists, we assume that judicial decisions are subject to personal biases, and that changing precedent is costly to judges....

We present a model of the creation of social networks, such as political parties, trade unions, religious coalitions, or political action committees, through discussion and mutual persuasion among their members. The key idea is that people are influenced by those inside their network, but not by...

We document two new facts about the distributions of answers in famous statistical problems: they are i) multi-modal and ii) unstable with respect to irrelevant changes in the problem. We offer a model in which, when solving a problem, people represent each hypothesis by attending "bottom up" to...