努力对机会不平等的影响:测度与比较  

The Effect of Effort on Opportunity Inequality:Measurement and Comparison

作　　者：龚锋[1] 李智[1] 雷欣[1] 

机构地区：[1]武汉大学经济与管理学院,邮政编码430072

出　　处：《经济研究》2017年第3期76-90,共15页Economic Research Journal

基　　金：国家社科基金重大项目(15ZDB158);国家自科基金面上项目(71573194);国家自科基金青年项目(71203167)的资助

摘　　要：本文致力于检验当全体居民的努力提高之后,由外部环境差异导致的收入分配机会不平等能否显著降低,从而回答"努力能否改变命运"的问题。具体而言,本文将CGSS样本按出生年代划分为"50后"、"60后"、"70后"和"80后"四个群体,采用基于随机参数Logit模型的倾向得分匹配方法(PSM),构造所有个体均付出最高努力时的"反事实"收入分布,测算并比较实际收入分布和"反事实"收入分布的机会不平等指数,从而检验努力提高能否改善收入分配的机会不平等程度。结果显示,四个出生年代居民的收入分配机会不平等占比达到35%-43%;当所有个体的努力达到最高程度时,"50后"居民的收入分配机会不平等仅降低4.98%,"60后"和"70后"居民机会不平等的降幅高达50%左右,而"80后"居民机会不平等则降低22%;优势和劣势环境群体因努力程度提高而实现的收入增长幅度不同,是不同出生年代机会不平等指数降幅存在明显差异的原因。本文认为,政府应致力于弱化外部环境的影响,提高努力的回报,对因外部环境不利而陷入贫困的居民进行重点救助,为弱势群体通过努力改变命运创建足够的平台和畅通的渠道。Summary： Nowadays, family background and social relations have become important factors affecting the development of individual careers, which not only damages social equity and justice, but also discourages economic growth. All Chinese people are chasing the Chinese Dream and want access to the same channels and platforms of upward flow. Thus, within the current social context, we ask whether disadvantaged groups can change their destinies through their effort. This question is tested from the perspective of inequality of opportunity to provide a quantitative foundation upon which the government can design a redistribution policy. Inequality of opportunity equates with income inequality resulting from environmental differences. The lower a disadvantaged individual＇s income distribution status, the greater the inequality of opportunity. Therefore, to determine whether effort can change one＇s destiny, we test a more workable proposition, that is, whether improving one＇s efforts can reduce the degree of one＇s inequality of opportunity. To this end, this paper divides the ＂ China General Social Survey＂ sample into four cohorts according to date of birth： 1950-1959, 1960-1969, 1970-1979 and 1980-1989. It then uses a nonparametric method with an ex post perspective to calculate the inequality of opportunity index based on the actual income distribution of the different age cohorts. The propensity score matching （ PSM ） method based on the random parameter Logit model is also used to construct the ＂ counterfactual＂ income distribution for all individuals when they are making their highest effort, and then to calculate and compare the difference in the inequality of opportunity between the real income and ＂ counterfactual＂ income distribution to determine whether improving effort can reduce inequality of opportunity. The empirical results show that with the efforts of all residents reaching their highest level, the inequality of opportunity among all four cohorts is reduced. However, the decl

关 键 词：环境 努力 机会不平等 “反事实”收入 随机参数PSM模型 

分 类 号：C913[经济管理]