教育在代际收入流动中的作用——基于中介效应分析的研究

The Role of Education in Intergenerational Income Mobility in China:Based on Mediation Analysis

教育是促进社会代际流动和个人阶层跃升的重要渠道。本文基于1995年、2002年、2013年和2018年中国家庭收入调查(CHIP)数据,在考虑了收入测量偏误和同住样本选择偏差的基础上,运用中介效应分析方法,研究了教育在我国居民代际收入流动中的作用。研究发现:(1)教育在我国居民代际收入流动中的作用约为13%,低于发达国家的这一数值。(2)教育对代际收入流动的影响存在异质性,对女性代际收入流动的作用远大于男性,对农业户口群体代际收入流动的作用略大于非农业户口群体。(3)在我国1970-1991年出生的群体中,教育对代际收入流动的作用持续减小。同时,教育的作用与代际收入流动性呈正向变动关系,即教育的作用越大,居民代际收入流动性越高。(4)教育发挥着减缓我国居民代际收入流动性下降的作用。(5)基于Heckman两步法的估计表明,不考虑同住样本选择偏差会导致教育作用的高估。研究表明,应提高教育质量及其均等化水平,并积极干预影响代际收入流动的非教育因素,以更好地实现教育促进代际收入流动的作用。

Education is an important channel to promote social intergenerational mobility and individual class.Based on the CHIP data of 1995,2002,2013 and 2018,and the correction of the measurement errors of income and the selection bias of co-residency,the paper uses the mediation analysis to study the role of education in intergenerational income mobility in China.The results show that:(1)the role of education in intergenerational income mobility is about 13%,which is lower than that in developed countries.(2)There is heterogeneity in the role of education in intergenerational income mobility.The role of education in intergenerational income mobility of women is much greater than that of men,and the agricultural Hukou is slightly greater than that of the non-agricultural Hukou.(3)Among the cohorts born in 1970-1991,the role of education in intergenerational income mobility remains decreasing.Meanwhile,there is a positive relationship between the role of education and intergenerational income mobility,that is,the greater the role of education,the higher the intergenerational income mobility.(4)Education plays a role in slowing down the decline of intergenerational income mobility in China.(5)Based on Heckman model,it is shown that the selection bias of co-residency will lead to the overestimation of the role of education.This research shows that we should improve the quality of education and its equalization level,and take active intervention in the non-educational factors,so as to promote the role of education in intergenerational income mobility.