健康冲击、社会资本与农户经济脆弱性——基于“CHIP2013”数据的实证分析

健康人力资本在农村经济中发挥着重要作用,农户健康受损时,会通过"劳动效应"、"挤占效应"和"情感效应"影响其经济脆弱性,而社会资本作为一种非正式机制,在血缘、地缘与业缘关系的连接下,通过及时获取信息与资源等对农户经济产生影响。文章利用"中国家庭收入调查2013"数据实证分析了健康冲击和社会资本对农户经济脆弱性的影响及作用机制。通过倾向得分匹配（PSM）和处理效应模型解决内生偏误问题、建立中介效应模型后,回归结果显示：健康冲击会通过挤占效应和情感效应两条渠道机制对农户经济产生负向影响,社会资本分项指标则通过信任渠道机制对农户经济产生正向影响;男性户主更易因遭受健康冲击而陷入经济脆弱困境,处于劳动年龄的户主在利用社会资本缓解经济脆弱性方面更具优势;而社会资本在缓解健康冲击对农户经济脆弱性中的作用并不显著,一个可能的原因是在农村社会中,社会资本等非正式机制逐渐被正式医疗保障机制所替代。在稳健性检验中,构造基于预期贫困定义的贫困脆弱性指标（VEP）进行替换变量回归,进一步证实所得结论。文章的政策涵义在于,应加强对于农户健康风险的管理,并重新挖掘社会资本在农村经济发展中的作用,从而缓解经济脆弱性,阻断贫困。

Health Shock,Social Capital and Household Economic Vulnerability in Rural Areas

As a kind of human capital, health plays an important role in rural economy. When a rural household's health is damaged, it's economic vulnerability will be intensified accordingly through labor effect, crowding-out effect and emotional effect; with the connection of blood, geopolitical and occupational relationships, the social capital, a kind of informal mechanisms, can affect the economy of rural households through the timely acquisition of information and resources. This paper empirically analyzes the impact and mechanism of health shock and social capital on the household's economy in rural China by using the data from "Chinese Household Income Project 2013". According to the feature of dependent variable, this paper constructs oprobit model, after solving the problem of endogenous bias by Propensity Score Matching (PSM) and treatment effect model, and testing the mediating effects by establishing mediating effect model. The conclusions are as follows:First, whether it is from the perspective of consumption and response to risk, there is a great probability that the health chock leads to the emergence of household vulnerability in rural areas, the conclusion remains unchanged after solving the problem of selection bias. Besides, health shock could affect the economic vulnerability of rural households through the two channels of crowding-out effect and emotional effect. Second, in the background of sequence and grade in rural China, by increasing rural households' consumption level or risk-responsiveness, the social capital of strong relationship and weak relationship, and the social capital of power could effectively mitigate the fragility of rural households. But in general, the overall effect of social capital on economic vulnerability is not so significant. We suppose that part of information is lost during the calculation of overall indicator of social capital. Third, male household owners are more economically vulnerable facing health shock and household owners of working age have more advantages in using social capital to alleviate economic vulnerability. Finally, when it comes to the moderating effect of social capital, the impact of alleviating health shock on household economic vulnerability is not significant, one possible reason is that with the development of modern economy, the traditional society order in villages has gradually disintegrated and the people become more indifferent. The association among rural households have been involved with more interests. At the same time, with the improvement of the rural medical security system, the informal mechanisms, such as social capital, have been gradually replaced by formal medical security mechanisms. In the part of robustness test, the construction of new indicator of rural household vulnerability is based on vulnerability as expected poverty (VEP) which means if afamily's poverty probability exceeds the given fragile line, the family is looked on as a vulnerable household. Then, the new indicator is used to reconstruct a regression and the result is the same as before. The policy implications of this paper are:The management of health risks for rural households should beattached great importance to, and the role of social capital in rural economic development should be re-examined so as to ease economic vulnerability, thus decreasing the probability of poverty.