机会公平环境的微观收入效应——来自人口迁移行为的证据

Micro Income Effects of An Opportunity Fairness Environment:Evidence from Migration Behavior

本文从代际流动视角探究了机会公平环境对居民收入的微观影响。通过匹配城市代际流动数据与微观人口数据,本文构造了反映人口在不同机会公平地区迁移状况的微观数据集,并基于人口迁移的因果识别策略,探讨了机会公平环境对个体收入的年均接触效应。结果表明,在机会公平程度高1个单位的城市每多驻留1年,个体收入排位将提高0.0408个百分位,且不同驻留年限的年均接触效应具有持续性和同质性。异质性分析表明,迁往机会更公平地区的个体存在显著的正向接触效应,迁往机会更不公平地区的个体则存在显著的负向接触效应,同时这种机会公平的正向接触效应更多存在于青年、高学历、城市户籍、高技能行业与非国有部门的个体中。机制分析显示,机会公平环境会显著促进个体融入,使用工单位更少排斥外来移民,提升了求职渠道市场化程度,进而带来正向接触效应。本文结论表明,构建机会公平的城市环境不仅有利于公平正义,也是优化城市人力资本配置、提升居民收入水平的重要途径。

Promoting social fairness and justice is an important manifestation of the core values of socialism.President Xi Jinping emphasized that comprehensively deepening reforms must take promoting social fairness and justice and im-proving people's well-being as the starting point and goal.The“fairness of opportunity”emphasized in the report to the 20th National Congress of the Communist Party of China(CPC)is an important way to achieve social fairness and justice,which helps individuals achieve higher-quality and fuller employment.Opportunity fairness means that individual development is less influenced by their parents and depends more on their abilities and efforts,and the distribution of human capital and income returns have a fairer market environment.It is not only about fairness but also about efficiency,which is crucial to high-quality economic development and the improvement of people's living standards.However,there remains a lack of sufficient theoretical explanation and micro-evidence on the impact of an opportunity fairness environment on economic efficiency,especially micro-individual income levels.To test the income effect of the opportunity fairness environment,it is necessary to use the exogenous changes of the opportunity fairness environment to identify its impact on individual income.The large-scale population migration since China's reform and opening up provides a quasi-natural experiment for this paper to test the impact of the environment of opportunity fairness on individual income.This paper uses the micro-data set formed by matching the 1%population sam-pling survey data in 2005 and the China Labor-force Dynamics Survey(CLDS)with the urban absolute intergenerational mobility data and uses for reference of Chetty&Hendren(2018)and Hull(2018)to construct a causal identification strategy based on population migration.Using the dual differences in migration decisions across different urban groups and the length of residence in new cities,this paper identifies the micro-level impact of the urban opportunity fairness environment on individual income levels.This paper comes to the following conclusions.First of all,the opportunity fairness environment has a significant contact effect on individual income and this contact effect has good continuity and homogeneity with the increase of residence time in the new environment.This conclusion is still valid after a series of robustness tests.Secondly,the heterogeneity analysis shows that there is a significantly positive contact effect among individuals who move to areas with fairer opportunities,while there is a significantly negative contact effect among individuals who move to areas with more unfair opportunities.At the same time,this positive contact effect of opportunity fairness is more prominent in individuals who have a young age,high levels of education,and urban household registration,and are in highly skilled industries and non-state-owned sectors.Thirdly,the mechanism analysis shows that the opportunity fairness environment significantly promotes the integration of individuals,and makes the employers less likely to exclude immigrants and the job search channels more market-oriented,which will bring about a positive contact effect.These indicate that building an urban environment with opportunity fairness is not only conducive to fairness and justice but also an im-portant way to optimize the allocation of urban human capital and improve the income of residents.The marginal contributions of this paper are as follows.Firstly,it explores the income effect of the opportunity fairness environment from a micro perspective,providing micro evidence on how a city's opportunity fairness environment affects residents'income,and proves its importance to social fairness,justice and economic efficiency.Secondly,it constructs a causal identification framework based on the migration identification strategy to overcome the endogenous bias caused by the self-selection of migration behavior and identify the average annual contact effect of the opportunity fairness environment on residents'income.Thirdly,it uses adult non-household migration samples to explore whether individuals can obtain economic benefits from a fairer environment through migration in the case of household registration restrictions in China.It not only has a stronger explanatory power for China's practical problems but also provides a factual basis for guiding the formulation of relevant decisions on migration or talent assistance.Fourthly,the conclusion of this paper proves that individuals may choose to move to areas with fairer opportunities out of economic rationality,thus revealing the internal economic logic of individuals moving to areas with fairer opportunities.