论文标题
富人的储蓄率的理论
A Theory of the Saving Rate of the Rich
论文作者
论文摘要
经验证据表明，富人比穷人具有更高的节省倾向。尽管这种观察似乎与偏好的同质性相矛盾，但从理论上讲，我们表明事实并非如此。具体而言，我们考虑了同型偏好和一般冲击的收入波动问题，并证明消耗功能是渐近线性的，具有渐近边缘倾向的精确分析表征（MPC）。我们为渐近MPC为零提供了必要和足够的条件。我们校准了一个具有标准恒定相对风险避免实用程序的模型，并表明零渐近MPC在经验上是可行的，这意味着我们的机制有可能适应数据中观察到的丰富和高财富不平等（小帕累托指数）的大量储蓄率。
Empirical evidence suggests that the rich have higher propensity to save than do the poor. While this observation may appear to contradict the homotheticity of preferences, we theoretically show that that is not the case. Specifically, we consider an income fluctuation problem with homothetic preferences and general shocks and prove that consumption functions are asymptotically linear, with an exact analytical characterization of asymptotic marginal propensities to consume (MPC). We provide necessary and sufficient conditions for the asymptotic MPCs to be zero. We calibrate a model with standard constant relative risk aversion utility and show that zero asymptotic MPCs are empirically plausible, implying that our mechanism has the potential to accommodate a large saving rate of the rich and high wealth inequality (small Pareto exponent) as observed in the data.
