Ricerc@Sapienza

Why do people keep their promises? Vanberg (2008) and Ederer and Stremitzer (2017) provide causal evidence in favor of, respectively, an intrinsic preference for keeping one's word and Charness and Dufwenberg's (2006) expectations-based account based on guilt aversion. The overall picture is incomplete though, as no study disentangles effects in a design that provides exogenous variation of both (the key features of) promises and beliefs. We report evidence from an experimental design that does so.