论文标题
了解小额信金扩展的分布方面
Understanding the Distributional Aspects of Microcredit Expansions
论文作者
论文摘要
为了消除极端贫困,正在实施各种贫困策略。一种这样的策略是增加了世界各地贫困地区的微循环。小额信贷(通常被定义为最初旨在旨在取代昂贵的本地贷款人的供应量不足的企业家的小贷款)的供应既受到赞扬又批评为开发工具(Banerjee等,2015b)。本文介绍了使用三个随机试验的数据增加访问微循环的异质影响的分析。本着认识到一般而言,政策干预的影响的精神是有条件的,尤其是在一组未知的因素上,我们研究异质性是否作为获奖者和失败者群体,以及此类子组是否在RCT之间具有特征。我们发现没有增加对消费水平微循环的访问量的影响,既没有平均分布也不是分布的证据。相反,缺乏对利润的平均影响似乎掩盖了异质的影响。但是,这些发现对应用的特定机器学习算法并不强大。从表现更好的弹性网转换为性能较差的随机森林,导致估计值的差异急剧增加。在这种情况下,评估Chernozhukov等人开发的相对性能机器学习算法的方法。 (2019年)为分析师提供了一种纪律处分的方式,以应对要部署哪种算法的不确定性。
Various poverty reduction strategies are being implemented in the pursuit of eliminating extreme poverty. One such strategy is increased access to microcredit in poor areas around the world. Microcredit, typically defined as the supply of small loans to underserved entrepreneurs that originally aimed at displacing expensive local money-lenders, has been both praised and criticized as a development tool (Banerjee et al., 2015b). This paper presents an analysis of heterogeneous impacts from increased access to microcredit using data from three randomised trials. In the spirit of recognising that in general the impact of a policy intervention varies conditional on an unknown set of factors, particular, we investigate whether heterogeneity presents itself as groups of winners and losers, and whether such subgroups share characteristics across RCTs. We find no evidence of impacts, neither average nor distributional, from increased access to microcredit on consumption levels. In contrast, the lack of average effects on profits seems to mask heterogeneous impacts. The findings are, however, not robust to the specific machine learning algorithm applied. Switching from the better performing Elastic Net to the worse performing Random Forest leads to a sharp increase in the variance of the estimates. In this context, methods to evaluate the relative performing machine learning algorithm developed by Chernozhukov et al. (2019) provide a disciplined way for the analyst to counter the uncertainty as to which algorithm to deploy.