Several recent papers argue that contracts provide reference points that affect ex post behavior. We test this hypothesis in a canonical buyer-seller relationship with renegotiation. Our paper provides causal experimental evidence that an initial contract has a highly significant and...

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 by the intention underlying this action. The theory...