效率与公平:高校扩招与高等教育回报的分位数处理效应

Efficiency and Equality: Expansion of Higher Education and the Quantile Treatment Effects of Return to Higher Education

无数文献对教育的均值效应进行了探讨和估计,现在人们更多地关注教育的分布效应,尤其关注的是教育对低收入者的影响。分位数回归模型是当前刻画条件分布最常用的模型,经典的分位数回归模型无法解决核心变量的内生性问题。本文以1999年中国高等教育扩招作为工具变量,基于Abadie等(2002)提出的条件QTE和Frolich and Melly(2014)提出的无条件QTE方法对中国高等教育回报的条件分布进行估计,解决了分位数回归中核心变量的内生性问题。研究结果表明,中国高等教育回报显著为正,而且随着收入水平提高,高等教育回报率下降,在高等教育扩招的同时存在着提升效率的"生产率效应"和改善收入分配的"公平效应"。

Many literatures concerned the mean effects of the return to education, and now more and more people take more attention to distributional effects. They are especially concerned about the impact of education on lowertail income people. Quantile regression model is the most commonly used model to characterize distributional effects, however, the classical quantile regression model can not solve the endogeneity problem of the variable of interest. Using the higher education expansion in 1999 as instrumental variable, this paper estimates the distributional effects of return to higher education based on conditional quantile treatment effect (QTE) provided by Abadie and et a(l. 2002)and unconditional quantile treatment effect provided by Frolich and Mell(y 2014). Both condtional QTE and unconditional QTE can solve the endogeneity problem of the variable of interest. The empirical results show that the return to higher education in China is significantly positive, and the return to higher education declines as the income level increases,meaning higher education can help more low-income people to raise their income level. The research of this paper has both theoretical and practical significance in Economics, as the results of this paper indicate that higher education expansion has both “productivity effect” to increase efficiency and “equality effect” to improve income distribution.