Contracting with Limited Commitment: Evidence from Employment-Based Health Insurance Contracts
研究发现工人流动性障碍能减少健康个体退出雇主保险池，形成事实上的承诺机制，使健康风险保险更充分；保险提供量与工人承诺程度正相关，说明承诺对长期合同设计的重要性，并为健康保险与就业捆绑提供新理由。
Impediments to worker mobility serve to mitigate the attrition of healthy individuals from employer-sponsored insurance pools, thereby creating a de facto commitment mechanism that allows for more complete insurance of health risks than would be possible in the absence of such frictions. Using data on health insurance contracts obtained from the 1987 National Medical Expenditure Survey, we find that the quantity of insurance provided is positively related to the degree of worker commitment. These results illustrate the importance of commitment in the design of long-term contracts, and provide an additional rationale for the bundling of health insurance with employment.