The Economic Returns to Social Interaction: Experimental Evidence from Microfinance
通过随机分配小额信贷客户到每周或每月还款小组，发现每周互动的小组在两年后更愿意与组员共担风险，且违约率降低三分之二，首次实验证明社交互动有经济回报。
Microfinance clients were randomly assigned to repayment groups that met either weekly or monthly during their first loan cycle, and then graduated to identical meeting frequency for their second loan. Long-run survey data and a follow-up public goods experiment reveal that clients initially assigned to weekly groups interact more often and exhibit a higher willingness to pool risk with group members from their first loan cycle nearly 2 years after the experiment. They were also three times less likely to default on their second loan. Evidence from an additional treatment arm shows that, holding meeting frequency fixed, the pattern is insensitive to repayment frequency during the first loan cycle. Taken together, these findings constitute the first experimental evidence on the economic returns to social interaction, and provide an alternative explanation for the success of the group lending model in reducing default risk. Copyright 2013, Oxford University Press.