【保险学术前沿】Quarterly Journal of Economics 2010—2019年保险类精选文章目录与摘要

声明：本系列文章基于原期刊目录和摘要内容整理而得，仅限于读者交流学习。如有侵权，请联系删除。

期刊介绍：

期刊介绍：《The Quarterly Journal of Economics》（经济学季刊）是经济学领域中历史悠久、最负盛名的期刊之一。它由哈佛大学经济系编辑，内容涵盖经济学领域的各个方面，对世界各地的经济学家、学者和学生来说是一个难以估量价值的期刊。该刊每年发行4期，每期发表文章12篇左右，2022-2023年影响因子为13.7。

本期看点：

●  私人医疗保险中，被保险人医疗支出在不同地区之间、相同地区的不同医院之间甚至相同医院的内部都有较大的差距。

●  员工一味倾向选择低免赔额医疗保险，不是计划菜单的复杂性驱动，也不是由告知避免高免赔额的偏好驱动，而是由员工对医疗保险的理解不足驱动的。

●  高免赔额导致医疗保险成本支出减少，主要是因为员工减少了各种医疗服务的使用数量，包括有潜在价值的医疗服务（如预防性服务）和有潜在浪费的医疗服务（如影像服务）。

●  在医疗保险中，被保险人滥用医疗服务，除了道德风险，还有另一个原因是“行为风险（Behavioral Hazard）”：即使患者的医疗成本很低，许多高价值的医疗服务的使用率仍然很低；即使患者需要承担全部成本时，也会购买一些无用的医疗服务。

●  公共医疗保险撤销后，会使得求职行为立即增加，就业和私人医疗保险覆盖率稳步上升，且存在“就业锁定（Employment Lock）”现象：为了获得企业提供的私人医疗保险覆盖而就业。

●  在经济衰退期间延长失业保险，不仅能增加失业保险覆盖率，还能减轻道德风险效应，从而在经济低迷时期带来更显著的社会效益。

Cooper, Zack 耶鲁大学；Craig, Stuart V. 宾夕法尼亚大学；Gaynor, Martin 卡内基梅隆大学、国家经济研究局；Van Reenen, John 麻省理工学院、经济绩效中心和国家经济研究局

摘要：We use insurance claims data covering 28% of individuals with employer-sponsored health insurance in the United States to study the variation in health spending on the privately insured, examine the structure of insurer-hospital contracts, and analyze the variation in hospital prices across the nation. Health spending per privately insured beneficiary differs by a factor of three across geographic areas and has a very low correlation with Medicare spending. For the privately insured, half of the spending variation is driven by price variation across regions, and half is driven by quantity variation. Prices vary substantially across regions, across hospitals within regions, and even within hospitals. For example, even for a nearly homogeneous service such as lower-limb magnetic resonance imaging, about a fifth of the total case-level price variation occurs within a hospital in the cross section. Hospital market structure is strongly associated with price levels and contract structure. Prices at monopoly hospitals are 12 percent higher than those in markets with four or more rivals. Monopoly hospitals also have contracts that load more risk on insurers (e.g., they have more cases with prices set as a share of their charges). In concentrated insurer markets the opposite occurs-hospitals have lower prices and bear more financial risk. Examining the 366 mergers and acquisitions that occurred between 2007 and 2011, we find that prices increased by over 6 percent when the merging hospitals were geographically close (e.g., 5 miles or less apart), but not when the hospitals were geographically distant (e.g., over 25 miles apart).

我们使用覆盖美国28%的拥有雇主发起医疗保险个人的保险索赔数据来研究被保险人医疗支出的变化、检验保险公司与医院合约的结构、并分析全国医院价格的变化。每个被保险受益人的医疗支出在不同地理区域相差3倍，与医疗保障制度（Medicare）支出的相关性非常低。对于被保险人来说，一半的支出变化是由地区间的价格变化驱动的，一半是由数量变化驱动的。价格在不同地区之间、地区内的不同医院之间甚至医院内部都存在大幅度变化。例如，即使对于几乎同质的服务，如下肢磁共振成像，也有大约五分之一的病例水平价格变化发生在医院的横截面内。医院市场结构与价格水平和合约结构密切相关。垄断医院的价格比有4个或更多竞争对手的市场高出12%。垄断医院的合约也给保险公司带来了更大的风险（例如，他们有更多按其收费比例确定价格的案例）。在更集中的保险市场中，情况恰恰相反，医院的价格更低且承担更多的财务风险。通过研究2007年至2011年间发生的366起并购事件，我们发现，当合并医院的地理位置较近（例如，相距5英里或更短）时，价格上涨了6%以上，但当医院的地理距离较远（例如，相距25英里以上）时，则价格没有上涨。

原文链接：https://academic.oup.com/qje/article-abstract/134/1/51/5090426?redirectedFrom=fulltext

Bhargava, Saurabh（卡内基梅隆大学）; Loewenstein, George（卡内基梅隆大学）; Sydnor, Justin（威斯康星大学）

摘要：We examine the health plan choices that 23,894 employees at a U.S. firm made from a large menu of options that differed only in financial cost-sharing and premium. These decisions provide a clear test of the predictions of the standard economic model of insurance choice in the absence of choice frictions because plans were priced so that nearly every plan with a lower deductible was financially dominated by an otherwise identical plan with a high deductible. We document that the majority of employees chose dominated plans, which resulted in excess spending equivalent to 24% of chosen plan premiums. Low-income employees were significantly more likely to choose dominated plans, and most employees did not switch into more financially efficient plans in the subsequent year. We show that the choice of dominated plans cannot be rationalized by standard risk preference or any expectations about health risk. Testing alternative explanations with a series of hypothetical-choice experiments, we find that the popularity of dominated plans was not primarily driven by the size and complexity of the plan menu, nor informed preferences for avoiding high deductibles, but by employees' lack of understanding of health insurance. Our findings challenge the standard practice of inferring risk preferences from insurance choices and raise doubts about the welfare benefits of health reforms that expand consumer choice.

我们研究了一家美国公司23,894名员工从一个大型选项菜单中的医疗计划选择，这些选项仅在财务成本分担和保费方面有所不同。在没有选择摩擦的情况下，这些决定为保险选择的标准经济模型的预测提供了一个清晰的测试。因为计划的定价方式是，几乎每个免赔额较低的计划在财务上都由一个在其他方面相同但具有高免赔额计划主导。我们记录到，大多数员工选择了主导计划，这导致了相当于所选计划保费24%的超额支出。低收入员工更倾向于选择主导型计划，大多数员工在接下来的一年中没有转向更具财务效益的计划。我们验证了，主导计划的选择不能通过标准的风险偏好或对医疗风险的任何预期来合理解释。通过一系列假设选择实验测试替代解释，我们发现主导计划的受欢迎程度主要不是由计划菜单的大小和复杂性驱动的，也不是由告知的避免高免赔额的偏好驱动的，而是由员工对健康保险的理解不足驱动的。我们的研究结果挑战了从保险选择中推断风险偏好的标准做法，并对扩大消费者选择的医疗改革福利效益提出了怀疑。

原文链接：https://academic.oup.com/qje/article-abstract/132/3/1319/3769420?redirectedFrom=fulltext

Zarek C. Brot-Goldberg（加州大学伯克利分校），Amitabh Chandra（哈佛大学），Benjamin R. Handel（加州大学伯克利分校），Jonathan T. Kolstad（加州大学伯克利分校）

摘要：Measuring consumer responsiveness to medical care prices is a central issue in health economics and a key ingredient in the optimal design and regulation of health insurance markets. We leverage a natural experiment at a large self-insured firm that required all of its employees to switch from an insurance plan that provided free health care to a nonlinear, high-deductible plan. The switch caused a spending reduction between 11.8% and 13.8% of total firm-wide health spending. We decompose this spending reduction into the components of (i) consumer price shopping, (ii) quantity reductions, and (iii) quantity substitutions and find that spending reductions are entirely due to outright reductions in quantity. We find no evidence of consumers learning to price shop after two years in high-deductible coverage. Consumers reduce quantities across the spectrum of health care services, including potentially valuable care (e.g., preventive services) and potentially wasteful care (e.g., imaging services). To better understand these changes, we study how consumers respond to the complex structure of the high-deductible contract. Consumers respond heavily to spot prices at the time of care, reducing their spending by 42% when under the deductible, conditional on their true expected end-of-year price and their prior year end-of-year marginal price. There is no evidence of learning to respond to the true shadow price in the second year post-switch.

衡量消费者对医疗护理价格的反应是健康经济学的核心问题，也是医疗保险市场优化设计和监管的关键要素。我们利用一家大型自保公司的自然实验，该公司要求其所有员工从提供免费医疗服务的保险计划转向非线性的高免赔额计划。这一转换导致全公司医疗总支出减少了11.8% 至 13.8%。我们将支出减少分解为（1）消费者按物定价、（2）数量减少和（3）数量替代三个部分，并发现支出减少完全是由于数量的直接减少。没有任何证据表明消费者在参加高免赔额保险两年后学会了按物定价。消费者减少了各种医疗服务的数量，包括有潜在价值的医疗服务（如预防性服务）和有潜在浪费的医疗服务（如影像服务）。为了更好地理解这些变化，我们研究了消费者如何应对高免赔额合同的复杂结构。消费者就医时对即期价格反应强烈，根据其真实的预期年终价格和上一年的年终边际价格，在该免赔额下他们的支出减少了 42%。在转换后的第二年，没有证据表明消费者学会了对真实影子价格做出反应。

原文链接：https://academic.oup.com/qje/article-abstract/132/3/1261/3769421?redirectedFrom=fulltext

Baicker, Katherine(哈佛大学); Mullainathan, Sendhil(哈佛大学); Schwartzstein, Joshua(哈佛大学)

摘要：A fundamental implication of standard moral hazard models is overuse of low-value medical care because copays are lower than costs. In these models, the demand curve alone can be used to make welfare statements, a fact relied on by much empirical work. There is ample evidence, though, that people misuse care for a different reason: mistakes, or "behavioral hazard." Much high-value care is underused even when patient costs are low, and some useless care is bought even when patients face the full cost. In the presence of behavioral hazard, welfare calculations using only the demand curve can be off by orders of magnitude or even be the wrong sign. We derive optimal copay formulas that incorporate both moral and behavioral hazard, providing a theoretical foundation for value-based insurance design and a way to interpret behavioral "nudges." Once behavioral hazard is taken into account, health insurance can do more than just provide financial protection--it can also improve health care efficiency.

标准道德风险模型的一个基本含义是，由于共付医疗费低于成本，低价值医疗服务会被过度使用。在这些模型中，仅需求曲线本身就可以用来做出福利分析，这是许多实证工作所依赖的事实。然而，有充分的证据表明，人们滥用医疗服务，还有另一个原因：失误或“行为危害”。即使患者的医疗成本很低，许多高价值的医疗服务的使用率仍然很低；即使患者需要承担全部成本时，也会购买一些无用的医疗服务。在行为危害存在的情况下，仅使用需求曲线的福利计算可能会相差数个数量级，甚至得到错误的符号。我们推导出了包括道德风险和行为危害的最佳共付额公式，为基于价值的保险设计提供了理论基础，并为解释行为“助推”提供了一种方法。一旦考虑到行为危害，医疗保险不仅可以提供财务保护，还可以提高医疗服务效率。

原文链接：https://academic.oup.com/qje/article-abstract/130/4/1623/1916415?redirectedFrom=fulltext

Garthwaite, Craig(西北大学); Gross, Tal(哥伦比亚大学); Notowidigdo, Matthew J. (芝加哥大学)

摘要：We study the effect of public health insurance on labor supply by exploiting a large public health insurance disenrollment. In 2005, approximately 170,000 Tennessee residents abruptly lost Medicaid coverage. Using both across- and within-state variation in exposure to the disenrollment, we estimate large increases in labor supply, primarily along the extensive margin. The increased employment is concentrated among individuals working at least 20 hours a week and receiving private, employer-provided health insurance. We explore the dynamic effects of the disenrollment and find an immediate increase in job search behavior and a steady rise in both employment and health insurance coverage following the disenrollment. Our results are consistent with a significant degree of "employment lock"--workers who are employed primarily to secure private health insurance coverage.

我们通过利用大规模的公共医疗保险撤销事件来研究公共医疗保险对劳动力供给的影响。2005年，大约有170,000名田纳西州居民突然失去了公共医疗保险。利用跨州和州内的不同撤销情况，我们估计劳动力供应将大幅增加，主要是沿深度边际(extensive margin)增长。增加的就业集中在每周至少工作20小时并接受由雇主提供私人医疗保险的个人中。我们探讨了公共医疗保险撤销的动态效应，发现撤销后求职行为立即增加、就业和私人医疗保险覆盖率稳步上升的现象。我们的结果与“就业锁定”现象有相当大程度的一致性——即那些主要为了获得私人医疗保险覆盖而就业的工人。

原文链接：https://academic.oup.com/qje/article-abstract/129/2/653/1867903?redirectedFrom=fulltext

Schmieder, Johannes F.（波士顿大学）; von Wachter, Till（加州大学洛杉矶分校）; Bender, Stefan（德国中央银行）

摘要：One goal of extending the duration of unemployment insurance (UI) in recessions is to increase UI coverage in the face of longer unemployment spells. Although it is a common concern that such extensions may themselves raise nonemployment durations, it is not known how recessions would affect the magnitude of this moral hazard. To obtain causal estimates of the differential effects of UI in booms and recessions, this article exploits the fact that in Germany, potential UI benefit duration is a function of exact age which is itself invariant over the business cycle. We implement a regression discontinuity design separately for 20 years and correlate our estimates with measures of the business cycle. We find that the nonemployment effects of a month of additional UI benefits are, at best, somewhat declining in recessions. Yet the UI exhaustion rate, and therefore the additional coverage provided by UI extensions, rises substantially during a downturn. The ratio of these two effects represents the nonemployment response of workers weighted by the probability of being affected by UI extensions. Hence, our results imply that the effective moral hazard effect of UI extensions is significantly lower in recessions than in booms. Using a model of job search with liquidity constraints, we also find that in the absence of market-wide effects, the net social benefits from UI extensions can be expressed either directly in terms of the exhaustion rate and the nonemployment effect of UI durations, or as a declining function of our measure of effective moral hazard.

在经济衰退时期延长失业保险（UI）期限的目的之一，就是在失业时间延长的情况下增加失业保险的覆盖面。尽管人们普遍担心这种延长本身可能会延长失业的持续时间，但经济衰退会如何影响这种道德风险的程度却不得而知。为了对失业保险在经济繁荣和衰退时的不同影响进行因果效应估计，本文利用了这样一个事实，即在德国，潜在的失业保险福利持续时间是确切年龄的函数，而这一函数本身在商业周期中是不变的。我们对 20 年的情况分别进行了断点回归，并将我们的估计值与商业周期的衡量指标相关联。我们发现，在经济衰退时，额外一个月的失业保险福利所产生的非就业效应充其量只是有所下降。然而，失业保险用尽率以及由此带来的额外覆盖范围在经济衰退期间显著上升。这两种效应的比值代表了工人受失业保险延期影响的概率加权后的非就业反应。因此，我们的研究结果表明，在经济衰退时期，延长失业保险的有效道德风险效应明显低于经济繁荣时期。通过使用一个具有流动性限制的求职模型，我们还发现，在没有全市场效应的情况下，延长失业保险的净社会效益既可以直接用失业保险用尽率和非就业效应来表示，也可以用我们衡量有效道德风险的递减函数来表示。

原文链接：https://academic.oup.com/qje/article-abstract/127/2/701/1825004?redirectedFrom=fulltext

Finkelstein, Amy（麻省理工学院）

摘要：In 2008, a group of uninsured low-income adults in Oregon was selected by lottery to be given the chance to apply for Medicaid. This lottery provides an opportunity to gauge the effects of expanding access to public health insurance on the health care use, financial strain, and health of low-income adults using a randomized controlled design. In the year after random assignment, the treatment group selected by the lottery was about 25 percentage points more likely to have insurance than the control group that was not selected. We find that in this first year, the treatment group had substantively and statistically significantly higher health care utilization (including primary and preventive care as well as hospitalizations), lower out-of-pocket medical expenditures and medical debt (including fewer bills sent to collection), and better self-reported physical and mental health than the control group.