中国寿险市场存在逆向选择吗?——来自CHARLS数据的经验证据

我国寿险市场是否存在逆向选择问题,在理论和实证两个方面缺乏细致的讨论。本文利用CHARLS数据和正相关理论检验了我国定期寿险和终身寿险市场中的逆向选择问题。我们选取了死亡率这一远期指标和健康状况这一近期指标来衡量消费者的死亡风险,从广延边际和集约边际两个方面利用正相关理论进行了深入的研究。实证结论表明,以死亡率和健康状况衡量的死亡风险与寿险消费负相关或者不相关,即我国寿险市场并不存在逆向选择问题。然后,我们讨论了模型的内生性问题,并根据年龄变量检验了结论的稳健性,实证结果表明我们的结论是稳健的。最后,本文利用双变量Probit模型设计了一个机制,并利用该机制验证了利他动机是我国寿险市场不存在逆向选择的原因之一。     

中国寿险市场存在逆向选择吗?——来自CHARLS数据的经验证据

我国寿险市场是否存在逆向选择问题,在理论和实证两个方面缺乏细致的讨论。本文利用CHARLS数据和正相关理论检验了我国定期寿险和终身寿险市场中的逆向选择问题。我们选取了死亡率这一远期指标和健康状况这一近期指标来衡量消费者的死亡风险,从广延边际和集约边际两个方面利用正相关理论进行了深入的研究。实证结论表明,以死亡率和健康状况衡量的死亡风险与寿险消费负相关或者不相关,即我国寿险市场并不存在逆向选择问题。然后,我们讨论了模型的内生性问题,并根据年龄变量检验了结论的稳健性,实证结果表明我们的结论是稳健的。最后,本文利用双变量Probit模型设计了一个机制,并利用该机制验证了利他动机是我国寿险市场不存在逆向选择的原因之一。     

金融创新如何缓解信任品市场失灵?——中国食品安全责任强制保险的自然实验

信任品市场(如食品、医药等)存在的问题一直困扰着中国和世界很多国家。关于产品和服务质量的信息不对称(道德风险和逆向选择)会导致信任品市场失灵。缓解信任品市场失灵,一种常见的解决方案是政府监管;而经济学家认为更加基于市场的解决方案(例如强制责任保险等金融创新)可能更为有效。在理论上,强制责任保险有两种相反的效应:保险公司的监督减少了道德风险 vs. 保险加剧了企业的道德风险,但一直亟待实证检验。幸运的是,中国食品安全责任强制保险的改革实验走在了世界的前列。本文利用了中国在不同地区、不同时间推行的这个自然实验,通过双重差分的方法识别出责任保险对于信任品市场的因果效应。本文的研究发现,强制责任保险能显著降低食品安全事故发生概率。这表明政府强制推行的金融创新可以成为信任品市场失灵的一种有效的替代性解决方案。     

A note on increased probability of loss and the demand for insurance

It is shown that the effect of increased probability of loss on the demand for insurance depends on whether both insured and insurer are aware of the change. When both insurer and insured share the same beliefs about the probability of loss (symmetric information), an increase in the loss probability may lead risk-averse agents to demandless insurance.     

An Insurance Market Simulation With Both Adverse and Advantageous Selection

The theory of adverse selection predicts that high‐risk individuals are more likely to buy insurance than low‐risk individuals if asymmetric information regarding individuals’ risk type is present in the market. The theory of advantageous selection predicts the opposite—a negative relationship between insurance coverage and risk type can be obtained when hidden knowledge in other dimensions (e.g., the degree of risk aversion) is present in addition to the risk type. Using the heterogeneity of insurance buyers in either risk type or risk aversion, we first introduce a classroom‐based insurance market simulation game to show that adverse selection and advantageous selection can coexist. We then explain the underlying concepts using two methods: a mathematical framework based on expected utility theory and an empirical framework based on the results of the game itself. The game is easy to implement, reinforces textbook concepts by providing students a hands‐on experience, and supplements current textbooks by bringing their content up to date with current research.     

Werbeanzeigen von Versicherungsunternehmen zur Aufklärung über Gesundheitsrisiken

Insurers offering health-related services as accident insurance, health insurance coverage or nursing insurance for instance have a legitimate interest in reducing costs of ill insured. Information about health-conscious behavior and health risks provided by advertisement may contribute this impact. In an experimental study, we analyze the effect of credibility of advertisement and independent third-party trustmark on health risk perception and health behavior intentions. Results demonstrate significant influence of credibility of advertisement on health risk perception and higher credibility for advertisement with independent trustmark. Furthermore, higher health risk perception conducts to healthier behavior intentions.     

从博弈论看保险市场信息不对称的本质及规范举措

博弈论是研究信息不对称问题的一种有效方法。保险业作为信息不对称最为集中的行业，保险人与被保险人之间存在着严重的信息不对称，特别是被保险人的逆向选择、道德风险和保险人的违规操作等现象普遍存在，长期困扰着保险界。     

Das deutsche und Schweizer Krankenversicherungssystem: Kosten,Leistungen und Anreizwirkungen aus Sicht der Versicherten

In the last years changes in the financing and in the service catalogue of the German health insurance system have been intensively discussed. The problematic incentive structures regarding the behaviour of the insured are frequently mentioned in these discussions. In particular, German insured have only little interest in a cost-efficient treatment of illness. At the same time the Swiss health insurance system is an example in which the insured show a higher cost consciousness. In the following article, the health insurance systems of Germany and Switzerland are compared from the perspective of the insured on the basis of the information-economic terms “moral hazard” and “adverse selection.” We find that both systems can learn from each other in reducing incentive problems.     

Econometric Methods for Testing for Asymmetric Information: A Comparison of Parametric and Nonparametric Methods with an Application to Hospital Daily Benefits

Since Chiappori and Salanié, testing for asymmetric information has become tantamount to testing for a positive relation between risk and coverage which is predicted by (equilibrium) models for adverse selection and moral hazard. In this paper we review parametric tests and a recently developed nonparametric test (Su and Spindler) and discuss the underlying assumptions. As an illustrative example, we apply the tests to hospital daily benefits which is part of the accident/disability insurance. We compare the results and show that the pattern of asymmetric information is mixed. The main finding is that we detect asymmetric information for low insured sums, but not for high insured sums which is a surprising result. We can also show that in certain ranges both types of test deliver similar results, while under certain circumstances, approaches using aggregation to binary variables might run into difficulties.     

Cream Skimming: Innovations in Insurance Risk Classification and Adverse Selection

We demonstrate how innovations in insurance risk classification can lead to adverse selection, or cream skimming, against insurers that are slow to adopt such pricing innovations. Using a model in which insurers with insufficient pricing data cannot differentiate between low‐ and high‐risk policyholders and therefore charge both the same premium, we show how innovative insurers develop new risk classification data to identify overcharged low‐risk policyholders and attract them from rival insurers with reduced prices. Less innovative insurers thus insure a growing percentage of high‐risk customers, resulting in adverse selection attributable to their informational disadvantage. Next, we examine two cases in which “Big Data” innovations in risk classification led to concerns about cream skimming among U.S. auto insurers. First, we track the rapid adoption of credit‐based insurance scores as pricing variables in personal auto insurance markets. Second, we examine the growing popularity of usage‐based insurance programs like telematics, plans in which insurers use data on policyholders’ actual driving behavior to set prices that attract low‐risk customers. Issues associated with the execution of such pricing strategies are discussed. In both cases, we document how rival insurers quickly adopt successful innovations to reduce their exposure to adverse selection.     

A Voluntary Deductible in Social Health Insurance with Risk Equalization: “Community‐Rated or Risk‐Rated Premium Rebate?”

On January 1, 2006 a new mandatory basic health insurance will be introduced in the Netherlands. One aspect of the new scheme is that the insured can choose to have a deductible. This option should increase the individual responsibility and reduce moral hazard. In the new scheme, a risk equalization system is aimed at avoiding preferred risk selection and insolvency of insurance companies with a relatively high‐risk pool. A crucial issue with respect to a voluntary deductible in this type of social health insurance is whether the premium rebate should be community rated or risk rated. The Dutch government has chosen the former, which means that the premium rebate will be independent of health status and risk. Our analysis shows that, in a situation with “accurate” risk equalization, a community‐rated premium rebate could lead to an adverse selection spiral. Over time, this spiral results in none of the insured taking a deductible and thus no reduction in moral hazard.     

Empirical Evidence for Advantageous Selection in the Commercial Fire Insurance Market

De Meza and Webb (2001) indicated that individuals with a higher degree of risk aversion would demand more insurance and invest in self-protection to reduce risk probability when both the preference type and investment in self-protection are hidden from insurers. They referred to the negative correlation between market insurance and risk type as advantageous selection. However, the relationship between risk type and the degree of risk aversion is debatable in both theoretical and empirical research. This paper therefore proposes that advantageous selection could be supported from another angle by directly examining the relationships that exist among market insurance, self-protection, and risk probability. By focusing on the commercial fire insurance market, information on the purchase of market insurance, investment in self-protection, and fire accident records is hand-collected by means of a unique survey. It is found that firms purchasing market insurance have a greater tendency to channel efforts into self-protection. It is also found that firms expending effort on self-protection are less likely to suffer a fire accident. Furthermore, it is found that firms with commercial fire insurance have less chance of suffering a fire accident than those without such insurance. Each of the above three findings jointly supports the view that advantageous selection could play a critical role in the commercial fire insurance market.     

Testing Adverse Selection With Two‐Dimensional Information: Evidence From the Singapore Auto Insurance Market

This article examines adverse selection in insurance markets with two‐dimensional information: policyholders’ riskiness and degree of risk aversion. We build a theoretical model to make equilibrium predictions on competitive insurance screening. We study several variations on the pattern of information asymmetry. The outcomes range from full separation to partial separation, and complete pooling of risk types. Next, we propose a copula approach to jointly examine policyholders’ coverage choice and accident occurrence in the Singapore automobile insurance market. Furthermore, we invoke the theory to identify subgroups of policyholders for whom one may expect the risk–coverage correlation and adverse selection to arise.     

The Incentive Effects of Increasing Per-Claim Deductible Contracts in Automobile Insurance

A new rating system of automobile insurance for vehicle damage in Taiwan was launched in 1996, introducing a deductible that increases with the number of claims. In this article, we provide a theoretical rationale for the existence of an increasing per‐claim deductible system and show that the new system is most likely an optimal choice for those insured who tend to have lower claims probability when incentives are present. Using a unique dynamic data set, we are able to conduct a natural experiment to examine the incentive effects (both positive and negative) by looking at the change in claim tendency before and after switching between two deductible plans: an increasing per‐claim deductible and a zero deductible. Our results provide direct evidence of the effects of deductible structures on claim behavior.     

Explaining Insurance Policy Provisions via Adverse Selection

In this article, we show that common insurance policy provisions—namely, deductibles, coinsurance, and maximum limits–can arise as a result of adverse selection in a competitive insurance market. Research on adverse selection typically builds on the assumption that different risk types suffer the same size loss and differ only in their probability of loss. In this study, we allow the severity of the insurance loss to be random and, thus, generalize the results of Rothschild and Stiglitz [1976] and Wilson [1977]. We characterize the separating equilibrium contracts in a Rothschild-Stiglitz competitive market. By further assuming a Wilson competitive market, we show that an anticipatory equilibrium might be achieved by pooling, and we characterize the optimal pooling contract.     

不同收入等级农村居民基本医疗保险受益公平性研究

公平普惠是我国卫生和健康事业建设的目标,基本医疗保险是实现目标的制度保障。本文基于安德森医疗服务利用行为理论,采用三阶段随机抽样方法采集湖北省少数民族贫困县965个农村参保者的调查数据,通过收入五等分法、二元选择模型和两部分模型对基本医疗保险受益公平性进行分析。结果发现:均等化的医疗保险政策不仅实现了规则公平,实践中也提高了低收入参保者的医疗服务利用行为,即低收入组与高收入组有相似的就诊行为,且最低收入组比最高收入组还有更高的报销可能性。但是从医疗服务利用结果和疾病经济负担来看,低收入者仍然处于劣势。最低收入组和较低收入组均比最高收入组有更高的慢性病患病可能性和更差的自我健康评价,同时低收入组有着更重的疾病经济负担。此外,少数民族居民、失业者、年长者、有配偶的居民可能有更差的医疗服务利用结果。因此,中国在实现全民医保的基础上,未来还要进一步提高医保受益公平性。     

Who Obtains Greater Discounts on Automobile Insurance Premiums?

Insurance purchasers obtain varied discounts for insurance. This paper examines what drives these differences, specifically whether the loss probability and the wealth of the insured affect the size of the premium discount in automobile insurance. To describe a bargain between a client and an insurer over premiums and coverage, we first develop a sequential insurance bargaining game where the client has an outside option to bargain with another insurer. We find that the equilibrium involves full coverage and, based on the results of comparative statics, we propose hypotheses regarding the effects of the loss probability and the wealth of the insured on the size of the premium discount. We then use a unique data set of 85,806 observations of Taiwanese automobile liability insurance for property damage to empirically test the predictions. After controlling for underwriting and macroeconomic variables, we find that both (1) the insured with a lower claim probability (as a proxy for the insured with a lower loss probability) and (2) the insured with a higher salvage value car (as a proxy for the wealthier insured) receive a greater premium discount. These results support our theoretical results.     

Credit lines as monitored liquidity insurance: Theory and evidence

We propose a theory of credit lines provided by banks to firms as a form of monitored liquidity insurance. Bank monitoring and resulting revocations help control illiquidity-seeking behavior of firms insured by credit lines. The cost of credit lines is thus greater for firms with high liquidity risk, which in turn are likely to use cash instead of credit lines. We test this implication for corporate liquidity management by identifying exogenous shocks to liquidity risk of firms in corporate bond and equity markets. Firms experiencing increases in liquidity risk move out of credit lines and into cash holdings.     

Moral hazard,adverse selection,and health expenditures: A semiparametric analysis

Theoretical models predict asymmetric information in health insurance markets may generate inefficient outcomes due to adverse selection and moral hazard. However, previous empirical research has found it difficult to disentangle adverse selection from moral hazard in health care consumption. We propose a two‐step semiparametric estimation strategy to identify and estimate a canonical model of asymmetric information in health care markets. With this method, we can estimate a structural model of demand for health care. We illustrate this method using a claims‐level data set with confidential information from a large self‐insured employer. We find significant evidence of moral hazard and adverse selection.     

老龄危机背景下我国长期护理保险制度试点方案的比较与思考

通过梳理15个试点地区长期护理保险制度的实施方案,对参保对象、基金来源、给付对象、评定依据、服务项目、服务形式以及待遇支付等进行比较分析。以老龄危机为背景,深入思考与探讨长期护理保险制度参保对象的覆盖、给付对象的界定、筹资主体的确定、保障内容的提供等问题,同时提出了针对性建议:参保对象应延伸至农村;给付对象暂定为重度失能失智老年参保者;筹资主体做到真正多元化;服务项目以生活照料为主;待遇水平体现出对居家护理的支持;给付形式引入现金给付。