逆向选择与伯川德竞争下两期保险准分离均衡

The Semi-Separating Equilibrium of Two-Stage Insurance under Bertrand Competition and Adverse Selection

多期保险作为单期保险自选机制的一种补充,是一种重要的动态风险分类方法,有利于规避逆向选择风险。在伯川德竞争假设下,研究两期保险准分离均衡存在的充要条件,建立了两期保险问题的不完全信息动态博弈模型,在分析投保人的激励相容约束以及个人合理性约束的基础上,推导出准分离均衡存在的充要条件,得到完全分离均衡与准分离均衡不可能同时存在的结论,并对均衡结果进行了边际分析。

Multi-period insurance as a supplement of self-selection mechanism of single-period insurance is an important dynamic risk classification methods,which is helpful to avoid the risk of adverse selection. Under the hypotheses of Bertrand competition,the necessary and sufficient conditions for the semi-separating equilibrium of two-stage insurance are studied. Firstly,the two-stage insurance incomplete information dynamic game model is established. And then,by analyzing the policyholders’ incentive compatibility constraint and individual rationality constraint,the necessary and sufficient conditions for semi-separating equilibrium are deduced,it is concluded that the fully separating equilibrium and the semi-separating equilibrium can not exist at the same time. At last,the marginal analysis to the semi-separating equilibrium is given.