中国保险业效率的实证分析

中国于2001年加入WTO,在2006年必须对外完全开放国内保险市场。然而,国内保险市场主要份额迄今仍由少数几家大型国有的或政府控制的公司所占有。由于国内保险市场欠发达,对保险的需要仍在呈现指数式上涨,所以对非国有的、海外的和合资保险公司来说存在着巨大的潜力、机遇和挑战。效率是政策制定者进一步鼓励保险业发展而关注的一个关键性因素。本文将集中探讨这个问题。本文使用了中国22家保险公司1999—2002年的一组数据,运用DEA方法评估了它们的效率分数,并应用一个计量经济学模型鉴别和确定了决定效率高低的主要因素。本文实证分析结果指出了提高保险公司效率的方向,并证明公司规模、所有制形式、营销方式和人力资本是影响保险公司效率的重要因素。本文的结论还为未来中国保险业发展的改革政策设计与执行提供了理论和经验支持。     

Innovation,competition and firm size distribution on fragmented markets

This paper presents a simple model of firm and consumer behavior. We formulate a sub-market entry game, where boundedly rational firms decide on investing in R&D for inventing new products that will appeal to targeted groups of consumers. The success depends on the amount of resources available for the project as well as on the firm’s familiarity with market characteristics. Successful innovation feeds back into the firm size and (potentially into) market knowledge and increases the future R&D productivity. A new product decreases the market-shares of incumbents. However, this business stealing effect is asymmetric across incumbent population. We identify the section of parameter space where firms have an incentive to diversify horizontally. In this section, the model results in rich industrial dynamics. Firm size heterogeneity emerges endogenously in the model. Equilibrium firm size distributions are heavy tailed and skewed to the right. The heaviness of the tail depends on submarket specificity of firm’s market knowledge. This relationship is non-monotonic, emphasizing two different effects of innovation on industrial dynamics (positive feedback and asymmetric business stealing).     

Optimal reinsurance policies with two reinsurers in continuous time

An optimal reinsurance problem of an insurer is studied in a continuous-time model, where insurance risk is partly transferred to two reinsurers, one adopting the expected-value premium principle and another one using the variance premium principle. The insurer aims to select an optimal reinsurance arrangement to minimize the probability of ruin. To provide an easy-to-implement solution to the problem, (semi)-explicit expressions for the optimal reinsurance strategies as well as the minimal ruin probabilities are derived for several claims distributions. Numerical studies including a real-data example based on the Danish fire insurance losses are provided to illustrate the solution of the problem. Our empirical results based on the Danish data reveal that the heavy-right-tailedness of claims distributions has a significant impact on the optimal reinsurance strategies and has a quite pronounced impact on the residual risk described by the minimal ruin probability.     

Costly risk verification without commitment in competitive insurance markets

This paper analyzes the equilibrium of an insurance market where applicants for insurance have a duty of good faith when they reveal private information about their risk type. Insurers can, at some cost, verify the type of insureds who file a claim and they are allowed to retroactively void the insurance contract if it is established that the policyholder has misrepresented his risk when the contract was taken out. However, insurers cannot precommit to their risk verification strategy. The paper analyzes the relationship between second-best Pareto-optimality and the insurance market equilibrium in a game theoretic framework. It characterizes the contracts offered at equilibrium, the individuals' contract choice as well as the conditions under which an equilibrium exists.     

Commitment to regulatory bureaucracy

A model is considered in which ‘regulatory bureaucracy’ is in the best interest of consumers as well as the regulated firm. Making it more costly for the regulator to discern the firm's true costs can help motivate the firm to act in the interest of consumers. But this is only true if the regulator cannot make binding precommitments concerning the use of his policy instruments. Endowed with the ability to precommit, prices below marginal cost, investment in excess of efficient levels, and the absence of regulatory bureaucracy will characterize the optimal regulatory policy.     

Pricing the Cost of Expropriation Risk

The paper examines a firm's cost of expropriation risk in a framework that links it to the government's incentive to expropriate. The author develops a pricing model for the firm's cost of expropriation risk that includes the positions of both government and firm. The government's decision to expropriate is modeled as an American-style call option. The cost of expropriation risk is modeled as the value of an insurance policy that pays off all losses resulting from expropriation. The firm's cost of expropriation risk is determined by the government acting to optimize the value of its option to expropriate. The author identifies the parameters that link the government's option to expropriate to the firm's cost of expropriation risk, and shows how the model can be used in capital budgeting decisions and the ongoing management of expropriation risk.     

Regulating a risk-averse firm under incomplete information

We examine the optimal regulatory policy for a risk-averse firm when the firm is imperfectly informed about its efficiency parameter for a project at the time of contracting. The firm’s risk aversion shifts the optimal regulatory policy from a fixed-price contract to a cost-plus contract. The optimal regulatory policy entails undereffort by an inefficient firm as in Laffont and Tirole (J Polit Econ 94(3):614–641, 1986) and the effort distortion increases as the firm becomes more risk-averse. Further, the regulator benefits from sequential contracting with the firm where the firm chooses contract terms gradually as it acquires information, albeit the benefit diminishes as the firm becomes more risk-averse.      

论全面风险管理对保险公司价值的影响

全面风险管理(Enterprise Risk Management,ERM)是一种最新的风险管理框架.它鼓励企业将风险进行整合,利用高度统一的方法来管理企业面临的所有风险.随着各个保险公司的风险意识的增强和监管部门对全面风险管理规定的出台,全面风险管理已经逐渐被保险公司的高层接受,并在公司内部开展不同形式的全面风险管理活动.本文针对目前保险公司开展全面风险管理活动的情况,分析了全面风险管理活动对保险公司价值的潜在影响,发现在全面风险管理选择模型中,企业规模与全面风险管理的使用成正相关.本文使用全面风险管理指示变量和其他一系列变量来考察全面风险管理使用与企业价值之间的内在关联,结果发现两者在统计和经济意义上存在着显著的正向关系     

Another Look at the Equity Risk Premium Puzzle

The model of Mehra and Prescott (1985, J. Econometrics, 22, 145–161) implies that reasonable coefficients of risk‐aversion of economic agents cannot explain the equity risk premium generated by financial markets. This discrepancy is hitherto regarded as a major financial puzzle. We propose an alternative model to explain the equity premium. For normally distributed returns and for returns far away from normality (but still light tailed), realistic equity risk premia do not imply puzzlingly high risk aversions. Following our approach, the ‘equity premium puzzle’ does not exist. We also consider fat‐tailed return distributions and show that Pareto tails are incompatible with constant relative risk aversion.     

Insurance and the behavior of competitive firms under revenue risks: a note

This paper re-examines the model of Ford, Mpuku, and Pattanaik [“Revenue Risks, Insurance, and the Behavior of Competitive Firms”.Journal of Economics 64 (1996): 233–246] wherein a risk-averse competitive firm faces insurable revenue risk. The optimal output and insurance cover of the firm are shown to be deterministically related in that the marginal costs of self-insurance and market insurance are equated. In response to increasing risk aversion, the firm always takes a higher insurance cover. Increasing fixed costs generate an income effect which induces the firm to take a higher insurance cover should the preference of the firm satisfy decreasing absolute risk aversion. Market insurance and self-insurance can be either substitutes or complements, depending on the shape of the variable insurance-premium schedule.     

A Model of Product Recalls with Asymmetric Information

This paper presents a model of involuntary product recall in which a firm has private information on its ability to produce safety. The ex post regulation of safety is motivated through a parametric imperfection in the product liability system which results in a firm under internalizing expected liability expenses. We treat the problem as one of mechanism design, where the regulator designs a recall procedure. This framework illuminates the point that recall is an interesting blend of ex ante and ex post regulation. We characterize a perfect recall procedure, contrast this with real world imperfect procedures, and study the interaction of the recall and the liability systems. Further, we analyze the interaction between optimal recall policy and product market structure.     

Regulation and information in a continuing relationship

Regulation typically involves a continuing relationship between a regulator and a firm, and that relationship is often complicated by asymmetric information. A multiperiod model of this relationship is analyzed in which a regulated firm has private information about its costs which may changed over time in a manner observable only to the firm. The regulator is assumed to be able to commit to a policy for the entire regulatory horizon, and the optimal pricing policy is shown to depend on an informativeness measure that indicates how information by the firm in one period will be used in future periods.     

Taxation and Life Insurance: A Theoretical Analysis*

Taxation of life insurance is generally considered to pose special and complex problems. These are alleged to stem from the special nature of life insurance. This paper challenges the notion that there is anything inherently special about the economics of life insurance and disputes the claim that it warrants special tax treatment. A model of the life insurance firm is presented and the appropriate basis for taxing life insurance companies and their policyholders is derived. This is compared with the system of taxation currently operating in Australia.     

基于PPP模式的海洋灾害保险合作模式分析

基于我国灾害救助以政府为主、商业性模式开发不足，且海洋灾害风险管理实践发展相对落后的现实，以PPP模式为雏形的灾害保险不失为一种有益的尝试。针对海洋灾害保险存在的信息不对称与主体地位不对等问题，在引入再保险机构、构建新的不对称PPP参与模式基础上，运用灰博弈模型对各主体参与的动态博弈过程及稳定策略进行分析，利用原保险与再保险双维灰博弈矩阵，求得各参数情形下的稳定策略，并对各情形下的稳定策略实现路径进行具体解析，为海洋灾害保险合作模式的达成提供进一步的决策参考     

Optimal Controls for a Large Insurance Under a CEV Model: Based on the Legendre Transform-Dual Method

The purpose of this paper is to consider the optimal proportional reinsurance and investment strategies for an insurance company. The insurer’s surplus process is approximated by a Brownian motion with drift. The insurance company can purchase proportional reinsurance and invest the surplus in a financial market which includes one risk-free asset and one risky asset whose price is modeled by a CEV model. The primary problem is changed to the dual problem by implying Legendre transform. When the objective of the insurance company is to maximize the expected logarithmic utility from terminal wealth, the closed-form expressions for the optimal reinsurance-investment policy which is different to the Merton case to the primal optimal problem are obtained and numerical simulations are provided to demonstrate our results. Moreover, we find an interesting result that risk exposure is non-monotonic in the cost of reinsurance.

     

An analysis of the conditions for the validity of Modigliani-Miller Theorem with incomplete markets

Summary In this paper we investigate the consequences of the firms' financial decisions in the framework of a perfectly competitive general equilibrium model with incomplete markets. When markets are complete or there are no derivative securities (such as options, forwards or futures) written on the firms' shares, these decisions are irrelevant. This result reaffirms and qualifies the original claim by Modigliani and Miller. On the other hand, if markets are incomplete, we show that in the presence of any type of derivative security a change in the capital structure of a firm will modify, generically, both the real equilibrium allocation and the value of the firm. The reason is that the payoff of the derivative securities is affected in a non-linear way by changes in the firm's financial policy; thus the set of the agents' insurance opportunities is also modified.The paper is a revised version of chapter 1 of my Ph.D. dissertation at Cambridge University. I wish to thank F. H. Hahn and H. M. Polemarchakis for their encouragement and very useful discussions. I am also grateful to J. Detemple, S. E. Satchell, S. Schaefer, P. Siconolfi, R. Stapleton, M. Subrahmanyam and three anonymous referees, as well as to participants at seminars at Cambridge, Columbia, EUI, Bocconi, USC, the R.E.S. Conference in Nottingham and the 6th World Congress of the Econometric Society in Barcelona for helpful comments. The usual disclaimer applies.     

Production and Abatement Distortions under Noisy Green Taxes

A pollution regulator seeking to maximize social surplus can be viewed as facing two efficiency problems. One is that, given abatement technology investment decisions, it should attempt to ensure that firms which should produce do produce and firms which should not produce do not produce. This ex-post efficiency problem is not trivial when there is noise concerning the extent of environmental damage a firm does. We use a Bayesian information framework to show that the regulator may find it efficient to tax a firm that reads as a high (low) damage polluter at less (more) than the damage reading. Unfortunately when an abatement decision has to be made, this ex-post efficient tax system also dampens the incentive to abate. In the absence of wrong-firm concerns, a regulator can solve the abatement problem by an ex ante declaration that taxes will not be adjusted for signal noise. However, the regulator has a commitment problem as such taxes may not be ex-post efficient. The most appropriate policy may involve a combination of instruments.     

Regulated absolute ruin problem with interest structure and linear dividend barrier

The uncontrolled surplus of an insurance company is a classical risk model. Now the risk model includes three features, namely debit interest, short-term and long-term invested interest, and linear dividend barrier. In this paper, the PDMP method and martingales are used for solvency studies in the risk model under regulation of minimum cash requirement. The integro-differential equations are derived for the expected discounted dividends under absolute ruin. In the case of exponential claim amounts, explicit expressions are obtained, as well as the numerical illustrations and their economic interpretation.     

美国寿险上市公司衍生金融工具应用的价值和业绩效应实证研究

本文运用Panel data模型实证检验衍生品的使用对美国寿险上市公司价值和业绩的直接效应,结果证明了衍生品运用之于寿险公司价值及业绩的正面效应,从而为我国衍生产品市场推出之后放开对寿险企业的投资准入提供了正面的实证依据。     

BANKING LICENCES, BAILOUTS AND REGULATOR ABILITY

I analyse a model in which it is socially optimal for banks to manage depositor funds but in which concerns about fraud discourage depositing and justify regulation. The regulator screens bankers and decides the level of charter value which they will receive as incentive to prevent fraud. She can also encourage deposits by insuring them. The optimal policy depends upon the regulator's screening ability: high ability regulators rely upon charter value and low ability regulators rely upon deposit insurance. I relate these findings to the regulation of transition economy banks, to operational risk management, and to banking competition policy.