Field evidence suggests that agents belonging to the same group tend to behave similarly, i.e., behavior exhibits social interaction effects. Testing for such effects raises severe identification problems. We conduct an experiment that avoids these problems. The main design feature is that each...

This paper presents a formal theory of reciprocity. Reciprocity means that people reward kind actions and punish unkind ones. The theory takes into account that people evaluate the kindness of an action not only by its consequences but also the intention underlying this action. The theory...

In many situations, people can lie strategically, for their own benefit. Since individuals differ with respect to their willingness to lie, the credibility of statements will crucially depend on who self-selects into such cheap-talk situations. We study this process in a two-stage political...