Pareto-Improving Social Security Reform when Financial Markets Are Incomplete!?
在随机生产和不完全市场下研究现收现付社会保障能否实现帕累托改进，发现忽略资本挤出效应时改革可改善代际风险分担，但一般均衡中的挤出效应会抵消收益。
This paper studies an overlapping generations model with stochastic production and incomplete markets to assess whether the introduction of an unfunded social security system leads to a Pareto improvement. When returns to capital and wages are imperfectly correlated, a system that endows retired households with claims to labor income enhances the sharing of aggregate risk between generations. Our quantitative analysis shows that, abstracting from the capital crowding-out effect, the introduction of social security represents a Pareto-improving reform, even when the economy is dynamically efficient. However, the severity of the crowding-out effect in general equilibrium tends to overturn these gains.