道德风险与基于委托-代理理论的最优保险契约模型

分别针对事后信息对称和存在道德风险的情况 ,使用委托—代理理论建立了相应的保险契约分析模型 ,对两种情况下的最优保险契约的性质进行了研究 .我们证明了信息对称时 ,最优保险契约要求完全保险 ,从而可以达到帕累托最优的风险分担 ,而且此时最优保险费等于意外事件造成损失的期望值 ;存在道德风险时 ,出于激励的目的 ,最优保险契约要求只提供部分保险 ,最优保险费小于意外事件造成的期望损失 ,而且随着意外事件造成损失的增大 ,投保人所遭受的实际损失也应该增大 .在两种情况下 ,最优保险费都与投保财产成反比.

The Optimal Insurance Contracts under Moral-hazard Based on the Principal-agent Theory

This paper employs the principal agent theory to research the optimal insurance contracts under moral hazard. We construct two principal agent models for non moral hazard and moral hazard respectively. The first model illustrates the most fundamental result: under the symmetric information, the optimal insurance contract requires full insurance coverage, and the optimal insurance premium is equivalent to the expected loss. The moral hazard model yields the general contractual forms that the market responds to moral hazard with partial insurance coverage, and the final loss suffered by insured individuals is increasing with the total loss aroused by the accidents, and the optimal insurance premium is less than the expected loss.