Conformity to descriptive norms

Descriptive norms, which measure the prevalence of prosocial behavior (prosocial “contribution”, in our context), powerfully influence individual prosocial choice. We investigate the relative importance of three channels through which this may occur: (1) Individuals directly prefer to conform to common behavior, (2) individuals reciprocally contribute to public goods when they expect others will also do their part, and (3), individuals learn that contribution is helpful given the descriptive norm. To separately identify these channels, we use a novel experimental setting that exogenously manipulates both beliefs about the descriptive norm and the relationship between descriptive norms and the public benefit to contribution, and whether contribution benefits the public good or a third-party recipient. We find that the preference for conformity dominates: Participants are strongly motivated to follow the descriptive norm even when the norm reveals that doing so is relatively unimportant. These findings have important implications for the design of social incentives.