Love me, love my dog: an experimental study on social connections and indirect reciprocity

This paper conducts a laboratory experiment to investigate the role of social connections in behavioral indirect reciprocity. We provide the evidence of spillovers effects of social ties, e.g., the recipient’s indirect reciprocal act varies with the relations between the donor and a third party. Naturally occurring friendship is employed to study social connections. Thus, a beneficiary might either be a “friend” or a “stranger” of the donor. We demonstrate that knowing social connections significantly increases the recipient’s repayment only if the donor is kind enough in the first place. Overall, recipients’ indirect reciprocity almost doubles when introducing social networks among donors and beneficiaries. It is also shown that this spillovers effect is unlikely the result of recipients’ perception of donors’ expectations. Major theories of social preferences, e.g., fairness, intention-based, guilt-aversion, cannot offer satisfactory explanations of our findings. We propose an explanation based on in-group and out-group differences but with endogenous group status, in which social connections play a crucial role.