Preference Effects on Friendship Choice: Evidence from an Online Field Experiment

Realized friendship choices result from the combined forces of not only personal preferences but also opportunity structures. Thus, it is not possible to infer preference effects from observed friendship data without invoking unrealistic assumptions about opportunity structures. In this paper, we report a study, based on an online field experiment, demonstrating the role of preference in friendship choice. Specifically, we test the influences of preferences in two dimensions: (1) identity homophily -- preference for other persons of the same or similar identity, and (2) status asymmetry -- preference for other persons of higher social status. We empirically tested these preference effects with an online field experiment in one of the largest social network service (SNS) websites in China. The results of our study confirm the preference effects on friendship choice in both of the two dimensions we tested.