逆向选择与伯川德竞争下两期保险完全分离均衡

摘要

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 control the risk of adverse selection. Under the hypotheses of Bertrand competition, the necessary and sufficient conditions for the fully separating equilibrium of two-stage insurance are studied. Firstly, the two-stage insurance dynamic game model is established. And then, by analyzing the policyholders' incentive compatibility constraint and individual rationality constraint, the necessary and sufficient conditions for fully separating equilibrium are deduced, and the only optimal fully separating equilibrium which conforms to the intuitive criterion is inferred. Furthermore, it is proved that the optimal fully separating equilibrium minimizes the signaling cost.%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,有利于控制逆向选择风险.在伯川德竞争假设下,研究两期保险完全分离均衡存在的充要条件.首先,建立了两期保险问题的动态博弈模型,然后,通过分析投保人的激励相容约束与个人合理性约束推导出完全分离均衡存在的充要条件,并在直观标准下对均衡结果进行精炼,论证结果表明,这一最优均衡使得信号传递成本达到最小.