The impact of smiling cues on social cooperation

While there is a plethora of experimental studies on the effects of preplay communication on economic behavior, little is known about the impact of simple cues, such as smiling, on pro‐sociality. This article presents a comprehensive analysis exploring how the presence of a smiling opportunity affects pro‐social behavior as measured by a one‐shot linear public goods game. Our design varies (i) whether smiling is costly or costless and (ii) whether one or both members in a group are given the opportunity to smile. To test for the robustness of our results, we consider two versions of smiling cues: (i) a smiling label and (ii) a smiling face (emoji). Our findings indicate that introducing a cost for smiling has detrimental behavioral consequences regardless of the cue. Specifically, when smiling is costly, only a small minority of subjects are willing to smile as opposed to when smiling is costless. As a result, subjects contribute significantly less. These results remain the same regardless of the type of smiling cue that subjects can send. Overall, our findings provide new evidence that simple cues such as smiles embody information that influences pro‐social behavior in social interactions.