基于事前非对称信息的带保证金的保险契约模型

Study of insurance contract model with cash deposit based on ex-ante asymmetric information

针对逆向选择常常导致保险市场交易的无效率问题,基于委托代理理论提出带保证金的保险契约模型,该模型首次将保证金作为信息甄别工具帮助保险公司更有效率地甄别投保人风险类型,达到规避逆向选择问题的目的.研究结果表明,带保证金的保险契约不劣于部分保险契约,并给出了前者相对于后者Pareto改进的充分条件.最后通过算例证实了带保证金的保险契约是已有典型保险契约的Pareto改进.

Adverse selection often leads to inefficiency in the insurance market. In order to solve the problem,this article establishes an insurance contract model with cash deposit based on the principal-agent theory. The contract adopts cash deposit as the information screening tool so that insurance companies can identify the risk-types of the policyholders more efficiently. None of the related literature before used cash deposit as a screening tool. The insurance contract with cash deposit is not inferior to the traditional ones and the sufficient conditions when this is a Pareto improvement are given;at last, a numerical example is presented to compare the utility of our model and those of other models and the result shows that the our model is more efficient.