经济转型期中国少数民族劳动力的大学教育收益率估算分析---兼评扩招政策对收入差距的影响

Estimation on the Rate of Return on University Education of the Chinese Ethnic Labor Force in the Transition Period--Evaluation on the Impact of Enrollment Expansion Policy on Income Gap

本研究采用北京师范大学收入分配研究院提供的家庭收入调查数据,利用普通最小二乘法、倾向得分匹配法以及分位数回归,估算转型发展时期中国少数民族劳动力的大学教育收益率,实证探讨扩招政策对收入差距的现实影响。结果发现:少数民族劳动力的整体教育收益率由1999年的7.8%上升到了2013年的9.4%,大学教育年收益率由扩招前的7.54%上升到了扩招后的8.83%,基准回归估计结果验证了高校扩招政策切实提高了少数民族劳动力的收入水平;利用倾向得分匹配纠正了教育选择的个体异质性后,大学教育处理效应落入[9.125%,15.025%]区间内,表明扩招政策并未降低少数民族劳动力的大学教育收益率,但忽视选择性偏差将会低估大学教育回报;条件分位数回归表明,扩招政策对高收入群体的增收效应大于低收入群体,当仅考虑人力资本因素时,扩招政策客观上扩大了少数民族的组内收入差距。

This study adopts the household income survey data provided by China Institute for Income Distribution of Beijing Normal University and uses OLS,PSM and Conditional Quantile Regression to estimate university education rate of return of Chinese minority ethnic labor force during the transition period and empirically explore the impact of the expansion policy on the income gap.The results showed that the overall rate of return on education of the ethnic labor force increased from 7.8%in 1999 to 9.4%in 2013,and the annual rate of return on university education increased from 7.54%before enrollment expansion to 8.83%after enrollment expansion.The results of the benchmark regression eatimation testified that the policy of expanding enrollment in colleges and universities improved the income level of ethnic labor force.After using propensity score matching to correct individual heterogeneity in educational choices,the treatment effect in colleges falls into the interval of[9.125%,15.025%],which indicates that the policy of expansion does not reduce the rate of return on higher education of the ethnic labor force,but neglecting the selective deviation will underestimate the return on college education.The conditional quantile regression analysis shows that the effect of the expansion policy on the high-income groups is greater than that of the low-income groups.When human capital factors are only considered,the expansion policy objectively expands the income gap within ethnic groups.