互联网金融领域"去专家化"的投资趋势正在凸显群体意见的重要性，而群体是否有智慧就是一个非常重要的话题。本文使用了中国一家P2P借贷平台的交易数据，借助构建的一个羊群行为指标研究了群体智慧对于违约率的预测。我们发现，在控制借款各项特征的情况下，随着羊群效应程度的增强，借款的违约率在下降。进一步的研究发现，对于两笔特征相似的借款，投资者羊群效应程度高的借款违约率显著低于未发生羊群效应的借款，因此投资者羊群效应程度可以为判别借款违约概率增加新的信息。久期分析的结果指出，在借款已经正常还款若干个月的条件下，投资者羊群效应程度高的借款在下个月发生违约的风险也会显著降低。总而言之，本文研究结果表明：在P2P网贷的投资中，群体是有智慧的，并且群体智慧能够提供新的信息。
The de-professionalized trend in Internet financial investment highlights the significance of crowd views, and the wisdom of crowd is increasingly attracting researchers' attention. The objective of this study to explore the predictive power of crowd views towards default rate by analyzing the evidence from P2P lending. The transaction data from Renrendai, a main P2P lending platform in China, is employed and the herding measure index of each loan is constructed for data analysis. It is found that the default rate of loan decreases as the herding effect of investors boosts under the control of all the other characteristics of loans and borrowers using Probit regression model. Further, regarding two loans with very similar characteristics, the loan with stronger herding effect is significantly less likely to default compared with the loan with weaker herding effect using the propensity score matching method. Herding, therefore, is informative in judging the probability to default. The duration analysis also indicates that loans with higher herding effect will significantly be less likely to default in the next month conditional on the loan repaid punctually for several months. With all the conclusion above, it is concluded that the crowd has wisdom in P2P investment and the wisdom of crowd offers new information to this investment. This conclusion is also helpful during investors' investment decisions process.
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