子女数量与代际收入流动

The Number of Children and Intergenerational Income Mobility

在我国人口增长乏力的严峻形势下,研究子女数量和代际收入流动的关系,为放开生育政策和实现共同富裕提供了借鉴意义。构建三期世代交叠模型,从理论上证实了子女数量与代际收入流动之间的正相关关系。利用2018年中国家庭收入调查数据进行实证检验,发现:(1)从整体分析,子女数量显著促进代际收入流动性提升,经过内生性处理和多种稳健性检验后,这一结论仍然成立;(2)从“数量-质量权衡”的角度,发现子女数量促进代际收入流动的影响存在异质性,对女儿、信贷发达市场和低收入群体的代际收入流动性的促进作用更强;(3)从代际流动方向分析,子女数量促进代际向上流动,抑制代际收入向下流动。由此可见,实现共同富裕,促进社会公平,需放开生育政策,提升子女数量。

Under the severe situation of population growth, studying the relationship between the number of children and intergenerational income mobility can provide reference for the opening of birth policy and the realization of common prosperity.This paper establishes a three-stage overlapping generation model and theoretically proves the positive correlation between the number of children and the intergenerational income mobility.Based on the data of 2018 China Household Income Project, the empirical test is conducted:(1)from the overall analysis, the number of children significantly promotes the improvement of intergenerational income mobility, and this conclusion remains valid after endogeneity treatment and multiple robustness tests;(2)from the perspective of “quantity-quality trade-off”,it is found that the number of children has a heterogeneous effect on intergenerational income mobility, and has a stronger promoting effect on the intergenerational income mobility of daughters, credit developed markets and low-income groups;(3)from the analysis of the direction of intergenerational mobility, the number of children promotes the upward mobility of intergenerational income and inhibits the downward mobility of intergenerational income. Thus,to achieve common prosperity and promote social equity,we need to relax the birth policy and increase the number of children.