Sources of Lifetime Inequality
研究终生不平等主要源于早年差异还是工作期间的运气差异，发现23岁时的初始条件比工作期间的冲击更能解释终生收入、财富和效用的差异。
Is lifetime inequality mainly due to differences across people established early in life or to differences in luck experienced over the working lifetime? We answer this question within a model that features idiosyncratic shocks to human capital, estimated directly from data, as well as heterogeneity in ability to learn, initial human capital, and initial wealth. We find that, as of age 23, differences in initial conditions account for more of the variation in lifetime earnings, lifetime wealth, and lifetime utility than do differences in shocks received over the working lifetime.