Disability Risk, Disability Insurance and Life-Cycle Behavior

这项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)计划的特点如何在明确的生命周期环境中影响消费和劳动力供应行为。对DI项目的分析是一个日益增长的研究主题，但它们仍然相对资金不足，研究不足。例如，失业保险(UI)是一个比失业保险更深入研究的项目，尤其是宏观经济学家和劳动经济学家。尽管2007年DI支付了总计991亿美元的现金福利，是UI的三倍，但这仍然是事实。DI项目也在快速增长。例如，1985至2007年间，接受直接投资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都同意，DI项目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，增加对合格残疾的定义的严格程度，并总体上减少所谓的DI道德风险问题的程度，即非残疾个人申请福利并被允许加入该计划。现有的经验文献确实发现了道德风险效应存在的令人信服的证据，这些证据大多基于简化形式的分析。例如，有大量文献记录了直接投资福利对直接投资申请的积极影响，以及参与人数的下降和残疾保险慷慨程度的上升之间的强烈相关性。另一方面，由于无法观察到真实的残疾状况，任何对该计划的访问限制都必然会拒绝为一些有资格的个人提供保险。一些现有的结构研究试图衡量实施DI计划的福利价值。我们从这些早期的论文中学到了很多。这一建议将开发一个丰富、现实的生命周期理论框架，并放松早期文献中所做的大多数简化假设。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，权衡该计划的低效与其提供的保险。特别是，它将评估该计划产生的对工作和储蓄的阻碍的重要性。它还计划使用这个框架来分析替代经济环境中的行为，特别是个体行为如何应对直接投资计划特征的变化(如降低计划的慷慨程度)或引入新的直接投资计划(如旨在让部分直接投资受益者重返工作岗位的政策)。拟议的模型试图在现实性和可行性之间取得平衡。它允许挽救生命周期和复杂的工资动态，理由是，鉴于申请直接投资福利的机会成本，以及健康也影响个人生产率的事实，当工资冲击是永久性的时，道德风险考虑应该比如果是暂时的更重要。拟议的偏好说明允许消费、休闲和健康状况之间的不可分割性(这意味着残疾消费的下降并不一定意味着福利损失，而是一种平稳跨州消费的方式)。最后，该模型考虑了直接投资计划和其他社会保险计划之间的互动，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。该模型被用来评估各种计划变化的福利效应：(A)增加残疾测试的严格性；(B)改变对残疾测试的重新评估的概率；(C)改变直接投资支付的累进程度；以及(D)降低工作成本或增加残疾人的就业机会等。更广泛的影响：在一个连贯的统一框架内评估上述变化的福利影响的能力具有重要的政策含义。其中一些变化被明确认为是对过去20年来直接投资扩张背后的道德风险问题的可能解决方案。这种扩张对该项目来说是一种直接成本，因为为该项目提供资金的个人较少。鉴于直接投资计划是社会保障体系的一部分，其预测的扩大对整个社会保障体系的长期可持续性具有重要影响。

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.