Old, Sick, Alone, and Poor: A Welfare Analysis of Old-Age Social Insurance Programmes
研究了针对老年人的经济状况调查型社会保险计划（如医疗补助和补充保障收入）的福利效应，发现这些计划能带来巨大福利收益，且美国当前规模偏小，扩大规模对穷人和富人均有益。
All individuals face some risk of ending up old, sick, alone, and poor. Is there a role for social insurance for these risks and, if so, what is a good programme? A large literature has analysed the costs and benefits of pay-as-you-go public pensions and found that the costs exceed the benefits. This article, instead, considers means-tested social insurance (MTSI) programmes for retirees such as Medicaid and Supplemental Security Income. We find that the welfare gains from these programmes are large. Moreover, the current scale of MTSI in the U.S. is too small in the following sense. If we condition on the current Social Security programme, increasing the scale of MTSI by 1/3 benefits both the poor and the affluent when a payroll tax is used to fund the increase.