The role of tracking and tolerance in relationship among friends

Friendship is a core aspect of human social life. Friends form long-term, cooperative relationships, and provide material and emotional support for one another. Previous research in social psychology suggests that people prefer balanced relationships over unbalanced relationship with friends, but at the same time, friendship is defined by an absence of direct reciprocity and careful tracking of favors given and received. The goal of this study was to distinguish between differences in tracking and tolerance of imbalances among friends and strangers. We conducted parallel behavioral economic experiments in three different urban cultural settings, USA, Japan and China, in an effort to expand our understanding of the dynamics of human friendship. Across all sites, we found that subjects monitored their friends less carefully than they monitored strangers, were more generous to friends than to strangers and that friends were more tolerant of imbalances in payoffs than strangers were. Although there were differences in the extent of tracking among friends and strangers, tracking did occur among friends. Our study extends the understanding on the dynamics of human friendship and emphasizes the need for further investigation on how friends balance vigilance and tolerance in real-life interactions.