农村居民收入及收入差距对农民健康的影响——基于地区比较的角度分析

Income,Income Inequality and Health in Rural China: the Analysis Based on Region

本文运用2000年2、004年及2006年的中国营养与健康调查数据,采用随机效应工具变量估计法,实证分析收入及收入差距对农民健康的影响,并测算了两者对农民健康地区差异的贡献份额。研究发现:第一,收入与健康存在内生性,随机效应工具变量估计的系数值是随机效应OLS估计的9.5倍,OLS估计低估了收入的影响;第二,东部及中西部地区收入对农民健康有显著的正向影响,收入差距对农民健康的影响呈U型,而考虑到基尼系数临界值大小,其对农民健康影响也呈正相关;第三,随着收入水平的提高,收入及收入差距对农民健康的边际影响递减,中西部地区大大高于东部地区,两者对缩小农民健康地区差异的贡献分别为25.7%和20.2%,而考虑到与收入相关的其它因素,农村收入因素的贡献达45.8%。因此,对于中西部欠发达农村地区来说,提高收入水平仍是提高农民健康的重要手段。

Using the data of China Health and Nutrition Survey（CHNS）from 2000 to 2006 and by the instrumental variable regression random effect modelt,he effect of income and income inequality on the health has been analyzed and the contribution of income and income inequality to the health disparity has been measured by comparing the two-different region in rural china.The result shows that the coefficient of income by IV estimator is 9.5 times of the ordinary ran-dom effect estimator,which underestimates the effect of income on health.The average household income has the significant positive effect on the health and income inequality has the inverted-U associated with health,but positive related also because of the critical value of ginii,n rural China.In addition tot,he marginal effect of income and income inequality to health in mid-western is more than that in eastern and the contribution of income and income inequality to health disparity between eastern and mid-western is 25.7 and 20.2 percent respectively,meanwhilet,he contribu-tion of the income is 45.8 percent by considering other related income factor.Therefore,we argue that how to improve income has an important to the heath in rural chinae,specially for mid-western.