AI 中文总结
本文构建带事后道德风险的动态模型，结合孟加拉国村级随机实验，发现小额信贷机构竞争明确减少高利贷信贷，新增机构在低饱和地区收益更大。
AI 中文摘要
经过数十年的小额信贷扩张，尽管收取更高的利率，高利贷者仍与小额信贷机构（MFIs）并存。我们构建了一个带有事后道德风险的动态模型，其中借款人将小额信贷机构的贷款用于生产，并在遭受冲击后可依赖高利贷者提供过渡性贷款，以偿还小额信贷机构并保留未来获得小额信贷信贷的机会。随后我们研究小额信贷机构的竞争如何塑造小额信贷机构与高利贷者之间的共存关系。竞争对小额信贷机构信贷的影响是模糊的：它可能削弱还款激励，或取代高利贷者成为过渡性贷款人。相比之下，竞争明确减少了高利贷者的信贷。在孟加拉国一项按基线小额信贷机构存在情况分层的村级随机扩张项目中，额外一家小额信贷机构会在两到三年后使高利贷贷款的数量减少约30%-40%，且对小额信贷机构或整体借贷无显著影响。这表明，在小额信贷机构主要依赖排斥威胁来诱导还款、而高利贷者提供应急融资的市场中，新增小额信贷机构进入的收益在饱和程度较低的地区可能更大。
英文摘要
After decades of microfinance expansion and despite charging higher interest rates, moneylenders continue to exist alongside microfinance institutions (MFIs). We develop a dynamic model with ex post moral hazard, in which borrowers use MFI loans for production and can rely on moneylenders for bridge loans after shocks to repay MFIs and preserve future access to MFI credit. We then study how MFI competition shapes the coexistence between MFIs and moneylenders. The effect of competition on MFI credit is ambiguous: it may weaken repayment incentives or replace moneylenders as bridge lenders. By contrast, competition unambiguously reduces moneylender credit. In a village-level randomized expansion in Bangladesh, stratified by baseline MFI presence, one additional MFI reduces the number of moneylender loans by roughly 30-40% two to three years later, with no detectable effect on MFI or overall borrowing. This suggests that, in markets where MFIs rely primarily on the threat of exclusion to induce repayment and moneylenders provide emergency finance, gains from additional MFI entry may be greater in less saturated areas.
