Multi-level Modeling of Social Roles in Online Micro-lending Platforms

In many teams, members play distinct roles, from leader to disrupter to social networker. Understanding the roles that contributors enact in micro-lending platforms is both psychologically and socially important for sustaining members' motivation and coordinating their joint efforts. Knowing what roles exist in these communities or which additional ones might be needed can also help teams function more effectively. In this paper, we identify social roles in Kiva.org, a peer-to-peer micro-funding platform, by utilizing members' lending behaviors, social network behaviors and communication behaviors to model their social roles at three levels. At the individual level, this method discovered active lenders who made many loans, early-bird lenders who made loans well before deadlines, and lurkers who rarely lent. At the topical level, our method differentiated those who had broad interests and lent to many causes from those who made loans only to borrowers in certain geographic regions or industry sectors. At the team level, the method revealed eight team-oriented functional roles such as encouragers, reminders, competitors, followers, and welcomers. To demonstrate the utility of the team roles, we used regression analysis to show how the distribution of social roles within teams influences the amount of money teams lent. Implications for identifying roles and understanding their contributions to teams are discussed.