Asymmetric information has been an important research object in the field of insurance economics. Adverse selection and moral hazard,which are caused by asymmetric information, tend to affect the efficiency allocation of market resources,resulting in low efficiency of the market and leading to market failure. Over the years,the domestic and foreign scholars have conducted extensive and in-depth theoretical analysis on adverse selection and moral hazard of insurance market, but the corresponding empirical test is less. At the same time, because moral hazard and adverse selection all show the feature of high risk high security, the traditional empirical test is difficult to distinguish the two.Taking the medical insurance market of China as an example, this paper tries to take a empirical test on adverse selection and moral hazard,which is based on the idea of correlation test on dynamic data, and studies the specific forms of asymmetric information in China. First of all, this paper summarizes the related research results at home and abroad, and analyzes the definitions, features and effects of adverse selection and moral hazard. Secondly, based on the theory of signal screening,this paper establishes the theoretical model of adverse selection and moral hazard respectively. Finally, based on the sample data, an empirical test on adverse selection and moral hazard of China’s medical insurance market is taken. The results show that,moral hazard and propitious selection phenomenon exist in medical insurance market of our country, but there is no adverse selection problem. At the same time, the correlation between risk and security, which is embodied by moral hazard(risk is positively related to the security) and propitious selection(risk is negatively related to the security), offset each other, leading to the result of traditional test on asymmetric information is not significant.This paper puts forward an ideal of taking correlation test based on dynamical data, and make an empirical research on the moral hazard and adverse selection. On the one hand, It is a supplement and verification of previous theoretical research, which can help to broaden the scope of the study. On the other hand, it provides a feasible solution to distinguish the adverse selection and moral hazard, which is a difficult problem for the previous empirical test, and discusses deeply on this issue. At the same time, this paper takes the medical insurance market of China as an example,conducting an empirical research on asymmetric information, and discusses the existence and forms of asymmetric information in medical insurance market, which may help to design more targeted policy and improve efficiency of the market. |