This paper analyzed the evolution of human capital inequality in an overlapping generations model that incorporates Stone–Geary preferences with subsistence consumption. Many studies have revealed an inverted U-shaped relationship between human capital inequality and economic development, namely the human capital Kuznets curve. However, this curve is inconsistent with empirical evidence in a US context, where the data suggest a U-shaped evolution of earnings inequality. We show that the utility function has an increasing elasticity of substitution, and the time allocated to human capital investment decreases in the early stages of human capital accumulation and increases afterward. Thus, we obtain a U-shaped curve for human capital inequality if the elasticity of substitution is large. Eventually, decreasing returns to human capital accumulation reduce inequality.

本文分析了在世代重叠模型中人力资本不平等的演变，该模型将 Stone-Geary 偏好与生计消费结合起来。许多研究揭示了人力资本不平等与经济发展之间的倒U型关系，即人力资本库兹涅茨曲线。然而，这条曲线与美国背景下的经验证据不一致，美国的数据表明收入不平等呈 U 型演变。我们表明效用函数具有增加的替代弹性，分配给人力资本投资的时间在人力资本积累的早期阶段减少，之后增加。因此，如果替代弹性很大，我们得到人力资本不平等的 U 形曲线。最终，