论文标题
人群,贷款,机器和偏见
Crowd, Lending, Machine, and Bias
论文作者
论文摘要
大数据和机器学习(ML)算法是许多金融科技创新的关键驱动力。虽然很明显,用机器代替人会提高效率,但尚不清楚机器是否以及何处可以比人类做出更好的决策。我们在人群贷款的背景下回答了这个问题,在传统上,一群投资者做出决定。使用Prosper.com的数据,我们表明,一种相当复杂的ML算法比人群投资者更准确地预测列表默认概率。对于高风险的清单,机器在人群中的优势更为明显。然后,我们使用机器做出投资决策,发现该机器不仅使贷方而且受益于借款人。当使用机器预测来选择贷款时,它会为投资者带来更高的回报率,并为借款人提供了更多替代资金选择的资金机会。我们还发现有暗示的证据表明,即使不使用性别和种族信息作为输入,该机器也对性别和种族有偏见。我们提出了一种通用有效的“贬低”方法,可以应用于任何以预测为重点的ML应用程序,并在我们的上下文中证明其使用。我们表明,与人群相比,较低的预测准确性的ML算法仍然会带来更好的投资决策。这些结果表明,ML可以帮助人群贷款平台更好地实现提供财务资源访问权限的承诺,以便其他服务不足的人并确保分配这些资源。
Big data and machine learning (ML) algorithms are key drivers of many fintech innovations. While it may be obvious that replacing humans with machine would increase efficiency, it is not clear whether and where machines can make better decisions than humans. We answer this question in the context of crowd lending, where decisions are traditionally made by a crowd of investors. Using data from Prosper.com, we show that a reasonably sophisticated ML algorithm predicts listing default probability more accurately than crowd investors. The dominance of the machine over the crowd is more pronounced for highly risky listings. We then use the machine to make investment decisions, and find that the machine benefits not only the lenders but also the borrowers. When machine prediction is used to select loans, it leads to a higher rate of return for investors and more funding opportunities for borrowers with few alternative funding options. We also find suggestive evidence that the machine is biased in gender and race even when it does not use gender and race information as input. We propose a general and effective "debasing" method that can be applied to any prediction focused ML applications, and demonstrate its use in our context. We show that the debiased ML algorithm, which suffers from lower prediction accuracy, still leads to better investment decisions compared with the crowd. These results indicate that ML can help crowd lending platforms better fulfill the promise of providing access to financial resources to otherwise underserved individuals and ensure fairness in the allocation of these resources.