The Incentive Complementarity Between Formal and Informal Enforcement
研究社区非正式交易与市场正式交易中执法机制的互补性，发现社区排斥市场欺诈者能同时增强两种交易的激励，且混合交易可能比单一模式更优。
Abstract We introduce a model in which people exchange some goods and services informally in their community and others formally on a market. We show that enforcement by informal communities and a formal market are complements: If communities ostracize individuals who are caught cheating on the market, this bolsters incentives to comply with exchanges in both settings. Although transactions within a community generate lower gains from trade than those on the wider market, the enhanced incentives from simultaneously transacting in communities and on the overall market can be welfare-enhancing compared with either extreme. We discuss the implications of informal community exchanges in a country’s development as well as how moral or religious beliefs enhance the complementarity between community and formal enforcement.