Social Image and Social Distance

Social image concerns motivate people to behave pro-socially if others are watching—as pro-social behavior leads to an update of the observer’s beliefs about the actor’s intrinsic pro-sociality. Thus, the effect of being observed depends on the magnitude of the shift in the observer’s beliefs. This, in turn, depends on the prior belief distribution. The more prior information available to the observer, the less effect new information has on posterior beliefs. This generates the novel hypothesis that the effect of observation on pro-social behavior increases with the social distance between the observer and the observed. Although people care more about what their friends think, they may be more motivated to impress a stranger who does not know them as well as a friend. We test this hypothesis in a field experiment. Participants were 670 high-school students who walked to generate donations for a public good. Participants were either unobserved, observed by a friend, or observed by another random participant. To identify social image concerns, we also manipulated whether effort up to a certain threshold yielded a personal benefit in addition to the public-good provision. The results provide support for the hypothesis, with age as a moderator.