英文文献：Social Security: Progressive Benefits but Regressive Outcome?-社会保障:渐进式福利，但递减结果?
英文文献作者：Monisankar Bishnu,Nick L. Guo,Cagri S Kumru
英文文献摘要：
In this paper, we study under what conditions a Pay As You Go (PAYG) type social security program can have regressive outcomes even though the benefits of this program are designed to be progressive. Since a PAYG social security program collects payroll taxes whenever agents are working, and it pays retirement benefits as long as retirees are alive, each individual's well being depends on how long they contribute to and receive payments from this program as well as how much. Empirical evidence suggests that agents who have low income tend to start working earlier and have shorter longevity than those with middle or high income. Implications of the low income groups' shorter mortality are examined both analytically and quantitatively in this paper. We find the conditions under which a PAYG social security program may have a regressive outcome in a simple two period partial equilibrium model. Afterwards, we created a large scale quantitative OLG model calibrated to the US economy to compare aggregate and welfare implications of the US type PAYG, a no progressive PAYG, and a means tested pension program. Our results indicate that incorporating differential mortality into account change the welfare implications.

在这篇论文中，我们研究了在什么情况下，即付即付(PAYG)式的社会保障计划会有累退的结果，即使这个计划的好处是被设计为渐进的。由于现收现付的社会保障计划在代理人工作的时候收取工资税，只要退休人员还活着，它就会支付退休福利，所以每个人的福祉取决于他们投入该计划的时间和从该计划中收到的款项的数量。经验证据表明，与中等或高收入的代理人相比，低收入代理人往往更早开始工作，寿命也更短。本文从分析和定量两方面研究了低收入群体较短死亡率的影响。在一个简单的两期部分均衡模型中，我们发现了现收现付社会保障计划的回归结果。随后，我们创建了一个以美国经济为基准的大规模定量OLG模型，以比较美国式现收现付制、无累进现收现付制和手段测试养老金计划的总和和福利影响。我们的结果表明，将不同的死亡率考虑在内会改变对福利的影响。