IDIOSYNCRATIC RISK,AGGREGATE RISK,AND THE WELFARE EFFECTS OF SOCIAL SECURITY

We ask whether a pay‐as‐you‐go financed social security system is welfare improving in an economy with idiosyncratic and aggregate risk. We show that the whole welfare benefit from insurance against both risks is greater than the sum of benefits from insurance against the isolated risks. One reason is the convexity of the welfare gain. The other reason is a direct risk interaction amplifying the utility losses from risk. Our quantitative evaluation shows that introducing a minimum pension leads to sizeable welfare gains, despite substantial crowding out. About 60% of these gains would be missing from summing up the isolated benefits.     

Anti-insurance: Analysing the Health Insurance System in Australia

This paper develops a model to analyse the Australian health insurance system when individuals differ in their health risk and this risk is private information. In Australia private insurance both duplicates and supplements public insurance. We show that, absent any other interventions, this results in implicit transfers of wealth from those most at risk of adverse health to those least at risk. At the social level, these transfers represent a mean preserving spread of income, creating social risk and lowering welfare – what we call anti-insurance. The recently introduced rebate on private health insurance can improve welfare by alleviating anti-insurance.     

Efficient Transfer of Aging Provisions in Private Health Insurance

In German-style private health insurance contracts, aging provisions are used to flatten premium profiles. An individual would like to change insurer if she perceives a low service quality. The first-best optimum is characterized by provision transfers upon insurer changes which are higher for high risks and may be negative for low risks. Should the actual risk status not be verifiable, provision transfers have to be uniform. Efficient transfers will equalize consumption across periods and states if high risks are deterred from switching. Otherwise, the optimum transfer balances the distortion of incentives for high-risk and low-risk individuals.     

Can a Mixed Health Care System be Desirable on Equity Grounds?*

Should health care provision be public, private, or both? We consider this question in a setting where people differ in their earnings capacity and face some illness risk. We assume that illness reduces an individual's time endowment when waiting for treatment. Treatment can be obtained in a competitive private sector (through private insurance) or in the National Health Service (NHS) where it is provided free of charge but after some (endogenous) waiting time. The equilibrium in the health care sector consists of a waiting time in the NHS such that no patient wants to switch health care provider. This equilibrium is governed by two public policies: the income tax system and the size of the NHS. We find that: (i) a mixed system with a small NHS is never desirable; (ii) actuarially fair sickness insurance is never desirable either; (iii) a mixed system with a sufficiently large NHS may improve on a pure public system if the dispersion of earnings capacities is large enough; and (iv) the welfare gains from such a mixed system are not likely to be significant.     

Quantitative analysis of health insurance reform: Separating regulation from redistribution

Two key components of the recent U.S. health reform are a new regulation of the individual health insurance market and an increase in income redistribution in the economy. Which component contributes more to the welfare outcome of the reform? We address this question by constructing a general equilibrium life-cycle model that incorporates both medical expenses and labor income risks. We replicate the key features of the current health insurance system in the U.S. and calibrate the model using the Medical Expenditures Panel Survey dataset. We find that the reform decreases the number of uninsured more than twice and generates substantial welfare gains. These welfare gains mostly come from the redistributive measures embedded in the reform, rather than from the regulatory changes.     

The extension of social security coverage in developing countries

We study the dynamic general equilibrium effects of introducing a social pension program to elderly informal sector workers in developing countries who lack formal risk sharing mechanisms against income and longevity risks. To this end, we formulate a stochastic dynamic general equilibrium model that incorporates defining features of developing countries: a large informal sector, private transfers as an informal safety net, and a non-universal social security system. We find that the extension of retirement benefits to informal sector workers results in efficiency losses due to adverse effects on capital accumulation and the allocation of resources across formal and informal sectors. Despite these losses recipients of social pensions experience welfare gains as the positive insurance effects attributed to the extension of a social insurance system dominate. The welfare gains crucially depend on the skill distribution, private intra-family transfers and the specific tax used to finance the expansion.     

Information Asymmetries and Risk Management in Healthcare Markets: The U.S. Affordable Care Act in Retrospect

This article critically examines the pertinent issues in ex ante and ex post moral hazard in healthcare markets, with the U.S. Affordable Care Act (ACA) as its focal point of inquiry. First, it compares the various types of information asymmetries resulting from the production, allocation, and utilization of health insurance. Second, it reviews the literature on adverse selection, moral hazard, and risk mitigation against which salient ACA reforms are analyzed. In contrasting conventional moral hazard from an alternative theory of welfare maximization, it suggests that healthcare (over)utilization cannot necessarily be considered wasteful, even if it ends up costing insurers more on a short-term basis. Costs and savings attributable to healthcare spending under the ACA will vary between the consumer, insurer, and regulator-subsidizer. Despite the ambiguities surrounding definitions of “health,” the challenge of containing inefficient moral hazard, and encouraging its desirable counterpart, lies in the tradeoffs that arise between consumer access to affordable and quality healthcare and the market competitiveness of health insurers. The new Trump administration will have to address these tradeoffs in repealing and replacing the ACA, particularly in light of escalating insurance premiums and deductibles, narrower provider networks, and technical implementation issues.     

What did Medicare do? The initial impact of Medicare on mortality and out of pocket medical spending

We study the impact of the introduction of one of the major pillars of the social insurance system in the United States: the introduction of Medicare in 1965. Our results suggest that, in its first 10 years, the establishment of universal health insurance for the elderly had no discernible impact on elderly mortality. However, we find a substantial reduction in the elderly's exposure to out of pocket medical expenditure risk. Specifically, we estimate that the introduction of Medicare was associated with a 40% decline in out of pocket spending for the top quartile of the out of pocket spending distribution. A stylized expected utility framework suggests that the welfare gains from such reductions in risk exposure alone may be sufficient to cover almost two-fifths of the costs of Medicare. These findings underscore the importance of considering the direct insurance benefits from public health insurance programs, in addition to any indirect benefits from an effect on health.     

社会医疗保障改革的福利效应:以中国城镇为例

This paper evaluates Chinese public health insurance reform enforced since 1998 in terms of its welfare effects. We evaluate China health insurance reform since 1998 using the China Health and Nutrition Surveys (CHNS) data with relevant econometric models. The results of empirical studies show that the public health insurance status has significant impact on medical service utilization and expenditure. The reform reduces the positive effect of public health insurance on medical service utilization, meaning the utilization gap is narrowed after the reform. However, the empirical studies find that the medical expenditure growth of the sample individuals in urban China has not been controlled after the Basic Medical Insurance (BMI) program even if a new co-payment is enforced. Two main reasons for this failure might be the rising cost of medical service and physician’s severe moral hazard, while both of them come from no managed care mechanism for medical service providers in China.      

Optimal Workfare with Voluntary and Involuntary Unemployment*

This paper addresses the welfare implications of introducing workfare into unemployment benefit policy. We consider a population composed of employed and unemployed workers and of individuals who do not seek employment. Job search behavior is unobservable, which means that voluntarily unemployed individuals can claim unemployment insurance (UI) benefits intended for unemployed workers. As a consequence, pecuniary benefit schemes underinsure workers against unemployment. We show that requiring unproductive activities (workfare) in exchange for UI benefits may generate a Pareto improvement by facilitating better unemployment insurance for workers, and we characterize the situations where this is the case.     

Medicare for all or medicare for none? A macroeconomic analysis of healthcare reform

In this study, I develop a novel general equilibrium life cycle model composed of finitely-lived households that differ according to age, skill level, and access to employer-provided health insurance. After introducing a “Medicare for all” health insurance system to the model, I examine how the welfare response to this policy change will differ according to household characteristics. Then, I compare this system to a completely privatized health insurance system that achieves universal health insurance coverage through the creation of utilization-based premium subsidies. In general, both systems tend to improve the welfare of young households at the expense of old households. However, when using average value-of-life as the primary measure of welfare, Medicare for all either benefits unskilled households at the expense of skilled households, or makes both worse off. In contrast, the privatized system improves the average value-of-life of all household groups, regardless of skill level or prior access to employer-provided health insurance.     

Employee cost-sharing and the welfare effects of flexible spending accounts

Flexible Spending Accounts (FSAs) subsidize out-of-pocket health expenses not covered by employer-provided health insurance, making health care cheaper ex post, but also reducing the incentive to insure. We use a cross section of firm-level data to show that FSAs are indeed associated with reduced insurance coverage, and to evaluate the welfare consequences of this shift. Correcting for selection effects we find that FSAs are associated with insurance contracts that have coinsurance rates about 7 percentage points higher, relative to a sample average coinsurance rate of 17%. Meanwhile, coinsurance rates net of the subsidy are approximately unchanged, providing evidence that FSAs are only welfare neutral if we ignore distributional considerations and the deadweight loss of the taxes necessary to finance the subsidy. These results also suggest that FSAs may explain a significant fraction of the shift in health care costs to employees that has occurred in recent years.     

The problem of the uninsured

The problem of the uninsured cannot be fully understood without considering the role of non-market alternatives to ‘market insurance’ called ‘self-insurance’ and ‘self-protection’ (SISP), including the public ‘health care safety-net’ system. We tackle the problem by formulating a ‘full-insurance’ paradigm that accounts for all four interacting insurance measures. We apply two versions of the full-insurance model to estimate, via calibrated simulations, the impacts of SISP on the fraction of uninsured, health spending, and health levels, and to assess how the mandated Affordable Care Act might affect these outcomes in comparison with the CBO projections in 2010. The results indicate that policy analyses which overlook the role of the real price of market insurance relative to the shadow prices of SISP in determining the decision to insure can grossly distort the capacity of mandated reforms like the ACA to insure the uninsured, contain overall health care costs, and improve health and welfare outcomes.     

Genetic Information: Comparing Alternative Regulatory Approaches When Prevention Matters

We compare the alternative approaches used for regulating genetic information in the health insurance market when prevention measures are available. In the model, firms offer insurance contracts to consumers who are initially uninformed of their risk type but can obtain such information by performing a costless genetic test. A crucial ingredient of our analysis is that information has decision‐making value since it allows for the optimal choice of a self‐insurance action (secondary prevention). We focus on the welfare properties of market equilibria obtained under the different regulatory schemes and, by using an intuitive graphical analysis, we rank them unambiguously. Our results show that Disclosure Duty weakly dominates the other regulatory schemes and that Strict Prohibition represents the worst regulatory approach.     

Insurance with Frequency Trading: A Dynamic Analysis of Efficient Insurance Markets

This paper extends existing insurance results on the type of insurance contracts needed for insurance market efficiency to a dynamic setting. It introduces continuously open markets that allow for more efficient asset allocation. It also estimates the role of preferences and endowments in the classification of risks, which is done primarily in terms of the actuarial properties of the underlying risk process. The paper further extends insurability to include correlated and catastrophic events. Under these very general conditions the paper defines a condition that determines whether a small number of standard insurance contracts (together with aggregate assets) suffice to complete markets or one needs to introduce such assets as mutual insurance. Journal of Economic Literature Classification Numbers: D81, D99, G11.     

Natural vs. financial insurance in the management of public-good ecosystems

In the face of uncertainty, ecosystems can provide natural insurance to risk averse users of ecosystem services. We employ a conceptual ecological-economic model in which ecosystem management has a private insurance value and, through ecosystem processes at higher hierarchical levels, generates a positive externality on other ecosystem users. We analyze the allocation of (endogenous) risk and ecosystem quality by risk averse ecosystem managers who have access to financial insurance, and study the implications for individually and socially optimal ecosystem management, and policy design. We show that while an improved access to financial insurance leads to lower ecosystem quality, the effect on the extent of the public-good problem and on welfare is determined by ecosystem properties. We derive conditions on ecosystem functioning under which, if financial insurance becomes more accessible, (i) the extent of optimal regulation increases or decreases; and (ii) welfare, in the absence of environmental regulation, increases or decreases.     

Investigating household choice for health and life insurance

The objective of this article is to investigate the joint determination of household choice for health and life insurance. Using the 2008–2009 Consumer Expenditure Survey data, we model household choice for health and life insurance assuming households consider purchasing them to manage financial risks in their life, after accounting for household characteristics, insurance characteristics, health status, and disability status. The model allows assessing the impact of health insurance choice on the choice of life insurance and the correlation between these two choices. The result suggests that health insurance choice positively affects the choice of life insurance and these two choices are positively correlated indicating complementary nature of these insurances in the basket of households’ risk minimising goods.     

Pareto efficient insurance contracts when the insurer's cost function is discontinuous

Summary. We consider the problem of efficient insurance contracts when the cost structure includes a fixed cost per claim. We prove existence of efficient insurance contracts and that the indemnity function in such contracts is non-decreasing in the damage. We further show that either there is no insurance, or the indemnity is positive for all losses, or efficient insurance contracts have a unique jump. We study variants of the model and provide a generalization to the case of non expected utilities. Our results are then applied to Townsend's model of deterministic auditing. Received: November 8, 2000; revised version: March 12, 2002 RID="*" ID="*" We are grateful to F. Salanié for pointing out an error in the previous version of the paper and for suggesting Proposition 6 to us. Correspondence to: R.-A. Dana     

More health care utilization with more insurance coverage? Evidence from a latent class model with German data

We analyse the impact of optional deductibles, private supplementary health insurance and income on the demand for health care utilization, measured as the number of physician visits with data from the German Socio-Economic Panel (SOEP). With a set of newly available variables for the years 2002, 2004 and 2006 that measure individual health more accurately and including risk-attitudes towards health we find that possible endogeneity of the insurance choice is not a problem. A latent class approach that takes into account the panel structure of the data reveals that especially individuals who have few doctor visits, the low users, respond strongest to insurance status and income. In this group we find that more insurance increases the demand for physician visits and there is a pro-rich inequity in health care utilization. No such effects are found for the high users.     

论巨灾期权及其演进

巨灾期权是以巨灾损失指数为基础而设计的期权合同,是保险公司通过在期权市场上缴纳一定期权费以购买在未来一段时间内的一种价格选择权。本文旨在对巨灾期权及其演进进行系统考察,以期对其有更为全面的认识。本文回顾了巨灾期权的市场发展;分析了ISO,PCS,GCCI和CHI四种指数为基础的巨灾期权产品和运作原理,考察了这四种巨灾指数及其产品的演进。