Disability Risk, Disability Insurance and Life-Cycle Behavior

该提案的目标是提供一个框架，以了解残疾风险和美国社会保障残疾保险（DI）计划的特点如何影响消费和劳动力供应行为，在一个明确的生命周期设置。 对DI项目的分析是一个日益增长的研究课题，但它们仍然相对缺乏资金和研究。例如，失业保险（UI）是一个比DI研究得更多的计划，特别是宏观经济学家和劳动经济学家。尽管2007年DI支付的现金福利总额为991亿美元，是UI的三倍。DI计划也在快速增长。例如，在1985年至2007年期间，接受直接保险的人口比例翻了一番，从覆盖人口的2.4%增加到4.7%。大多数研究人员现在同意，DI计划正在以不可持续的速度增长。整个美国社会保险体系的财务可持续性可能会受到影响。最近DI计划规模的增长再次呼吁重新设计该计划，旨在减少福利慷慨，增加合格残疾定义的严格性，并在总体上减少DI的道德风险问题，即，非残疾人申请福利并获准加入该方案。现有的实证文献确实发现了令人信服的证据，道德风险效应的存在，主要是基于简化形式的分析。例如，有大量文献记载了残疾保险福利对残疾保险申请的积极影响，以及残疾保险参与率下降与慷慨程度提高之间的密切相关性。另一方面，由于真实的残疾状况无法观察，对参加该方案的任何限制必然会使一些应得的个人无法获得保险。现有的一些结构性研究试图衡量实施直接投资计划的福利价值。从这些早期的论文中我们学到了很多，这个建议将发展一个生命周期理论框架，这个框架是丰富的，现实的，并且放松了早期文献中的大部分简化假设。它将估计模型的参数，然后使用这个理论框架来评估替代政策，将该计划的低效率与其提供的保险进行加权。特别是，它将评估该计划产生的工作和储蓄抑制因素的重要性。此外，还计划利用该框架分析在其他经济环境下的行为，具体而言，分析个人行为如何应对直接投资项目的特征变化（如减少项目的慷慨性）或新的政策的引入（如旨在使部分直接投资受益人重返工作岗位的政策）。它考虑到生命周期的节约和复杂的工资动态，理由是，考虑到申请直接投资福利的机会成本以及健康也影响个人生产力的事实，当工资冲击是永久性的而不是暂时性的时，道德风险的考虑应该更相关。拟议的偏好规范允许消费、休闲和健康状况之间的不可分离性（这意味着残疾消费下降并不一定表明福利损失，而是一种使各州消费平稳的方式）。最后，该模型考虑到DI计划和其他社会保险计划之间的相互作用，以及劳动力市场摩擦。模型的结构参数将使用间接推断和来自SIPP和PSID的纵向数据来确定。该模型用于评估各种方案变化的福利效果：（a）提高残疾测试的严格性;（B）改变残疾人保险重新评估的可能性;（c）改变残疾人保险支付的累进性;（d）降低残疾人的工作成本或增加残疾人的就业机会等。在一个连贯统一的框架内评估上述变化的福利影响的能力具有重要的政策意义。其中一些变化已被明确认为是可能的解决方案的道德风险问题的基础上扩大直接投资卷的过去二十年。这一扩张是该计划的直接成本，因为为该计划提供资金的个人减少了。由于直接保险计划是社会保障制度的一部分，其预测的扩展对整个社会保障制度的长期可持续性具有重要意义。

The goal of this proposal is to provide a framework for understanding how disability risk and the features of the Social Security Disability Insurance (DI) program in the US affect consumption and labor supply behavior in an explicit life-cycle setting. Analyses of the DI program are a growing topic of research, but they are still relatively underfunded and understudied. For example, Unemployment Insurance (UI) is a much more studied program than DI, especially by macro and labor economists. This is despite the fact that in 2007 DI paid cash benefits totaling $99.1 billions, three times more than UI. The DI program is also growing very fast. For example, between 1985 and 2007 the proportion of people on DI doubled, from 2.4 of the covered population to 4.7 percent. Most researchers now agree that the DI program is growing at unsustainable rates. The financial sustainability of the whole U.S. social insurance system may be affected. The recent growth in the size of the DI program has renewed the calls for a redesign of the program aimed at reducing benefits generosity, increasing strictness in the definition of a qualifying disability, and in general reducing the extent of what is known as the moral hazard problem of DI, i.e., non-disabled individuals applying for benefits and being admitted into the program. The existing empirical literature has indeed found convincing evidence for the existence of moral hazard effects, mostly based on reduced form analyses. For example, there is a large literature documenting a positive effect of DI benefits on DI application and a strong correlation between fall in participation and rise in generosity of disability insurance. On the other hand, due to the unobservability of the true disability status, any restriction in the access to the program would necessarily deny insurance to some deserving individuals. Some of the existing structural studies have tried to measure the welfare value of having the DI program in place. A lot has been learned from these earlier papers.This proposal would develop a life-cycle theoretical framework that is rich, realistic, and relaxes most of the simplifying assumptions made in the earlier literature. It would estimate the parameters of the model and then use this theoretical framework to evaluate alternative policies weighting the inefficiency of the program against the insurance it provides. In particular, it would evaluate the importance of the disincentives to work and save generated by the program. It would also plans use this framework to analyze behavior in alternative economic environments, specifically, how individual behavior responds to changes to the features of the DI program (such as making the program less generous) or to the introduction of new ones (such as policies aimed at moving some DI beneficiaries back to work).The proposed model tries to strike a balance between realism and feasibility. It allows for life cycle saving and complex wage dynamics, on the ground that, given the opportunity cost of applying for DI benefits and the fact that health also affects individual productivity, moral hazard considerations should be more relevant when wage shocks are permanent than if they are temporary. The proposed preference specification allows for non-separability between consumption, leisure and health status (this means that a fall of consumption on disability does not necessarily indicate a welfare loss, but a way to smooth consumption across states). Finally, the model allows for interactions between the DI program and other social insurance programs, as well as labor market frictions. Structural parameters of the model will be identified using Indirect Inference and longitudinal data from SIPP and PSID. The model is used to evaluate the welfare effect of various program changes: (a) Increasing the strictness of the disability test; (b) Changing the probability of re-assessment for DI; (c) Changing the progressivity of DI payments, and (d) Reducing the costs of work or increasing job opportunities for people with disabilities, etc.Broader impact: The ability to evaluate the welfare effect of the changes above in a coherent unified framework has important policy implications. Some of these changes have been explicitly considered as possible solutions to the moral hazard problem underlying the expansion of DI rolls of the last two decades. This expansion represents a direct cost for the program because fewer individuals contribute to its financing. Given that the DI program is part of the Social Security system, its forecast expansion has important implications for long-term sustainability of the Social Security system as a whole.