中国再保险业发展中的供需问题研究

我国的再保险业刚刚起步 ,承保能力不足 ,技术、服务水平不高 ,对于商业分保还很陌生。尽管如此 ,目前再保险市场的大门已经打开 ,而且根据我国的承诺 ,四年后法定分保将不复存在 ,对于以法定分保为支撑的中国再保险公司和中国再保险业而言 ,如何在较短的时间内发展、壮大是一个严峻的挑战。笔者以为 ,缩小再保险供需之间的巨大缺口是当务之急 ,因此应做好相应的工作。     

Optimal Proportional Reinsurance Policies in a Dynamic Setting

We consider dynamic proportional reinsurance strategies and derive the optimal strategies in a diffusion setup and a classical risk model. Optimal is meant in the sense of minimizing the ruin probability. Two basic examples are discussed.     

On the optimality of proportional reinsurance

Proportional reinsurance is often thought to be a very simple method of covering the portfolio of an insurer. Theoreticians are not really interested in analysing the optimality properties of these types of reinsurance covers. In this paper, we will use a real-life insurance portfolio in order to compare four proportional structures: quota share reinsurance, variable quota share reinsurance, surplus reinsurance and surplus reinsurance with a table of lines.     

Reinsurance contract design with adverse selection

ABSTRACT

In light of the richness of their structures in connection with practical implementation, we follow the seminal works in economics to use the principal–agent (multidimensional screening) models to study a monopolistic reinsurance market with adverse selection; instead of adopting the classical expected utility paradigm, the novelty of our present work is to model the risk assessment of each insurer (agent) by his value-at-risk at his own chosen risk tolerance level consistent with Solvency II. Under information asymmetry, the reinsurer (principal) aims to maximize his average profit by designing an optimal policy provision (menu) of ‘shirt-fit’ reinsurance contracts for every insurer from one of the two groups with hidden characteristics. Our results show that a quota-share component, on the top of simple stop-loss, is very crucial for mitigating asymmetric information from the insurers to the reinsurer.     

Reinsurance premium principles based on weighted loss functions

ABSTRACT

In this paper, we propose new reinsurance premium principles that minimize the expected weighted loss functions and balance the trade-off between the reinsurer's shortfall risk and the insurer's risk exposure in a reinsurance contract. Random weighting factors are introduced in the weighted loss functions so that weighting factors are based on the underlying insurance risks. The resulting reinsurance premiums depend on both the loss covered by the reinsurer and the loss retained by the insurer. The proposed premiums provide new ways for pricing reinsurance contracts and controlling the risks of both the reinsurer and the insurer. As applications of the proposed principles, the modified expectile reinsurance principle and the modified quantile reinsurance principle are introduced and discussed in details. The properties of the new reinsurance premium principles are investigated. Finally, the comparisons between the new reinsurance premium principles and the classical expectile principle, the classical quantile principle, and the risk-adjusted principle are provided.     

Optimal proportional reinsurance with a loss-dependent premium principle

ABSTRACT

Empirical studies suggest that many insurance companies recontract with their clients on premiums by extrapolating past losses: a client is offered a decrease in premium if the monetary amounts of his claims do not exceed some prespecified quantities, otherwise, an increase in premium. In this paper, we formulate the empirical studies and investigate optimal reinsurance problems of a risk-averse insurer by introducing a loss-dependent premium principle, which uses a weighted average of history losses and the expectation of future losses to replace the expectation in the expected premium principle. This premium principle satisfies the bonus-malus and smoothes the insurer's wealth. Explicit expressions for the optimal reinsurance strategies and value functions are derived. If the reinsurer applies the loss-dependent premium principle to continuously adjust his premium, we show that the insurer always needs less reinsurance when he also adopts this premium principle than when he adopts the expected premium principle.     

Optimal reinsurance under general law-invariant risk measures

In recent years, general risk measures play an important role in risk management in both finance and insurance industry. As a consequence, there is an increasing number of research on optimal reinsurance decision problems using risk measures beyond the classical expected utility framework. In this paper, we first show that the stop-loss reinsurance is an optimal contract under law-invariant convex risk measures via a new simple geometric argument. A similar approach is then used to tackle the same optimal reinsurance problem under Value at Risk and Conditional Tail Expectation; it is interesting to note that, instead of stop-loss reinsurances, insurance layers serve as the optimal solution. These two results highlight that law-invariant convex risk measure is better and more robust, in the sense that the corresponding optimal reinsurance still provides the protection coverage against extreme loss irrespective to the potential increment of its probability of occurrence, to expected larger claim than Value at Risk and Conditional Tail Expectation which are more commonly used. Several illustrative examples will be provided.     

Optimal excess-of-loss reinsurance contract with ambiguity aversion in the principal-agent model

ABSTRACT

We discuss an optimal excess-of-loss reinsurance contract in a continuous-time principal-agent framework where the surplus of the insurer (agent/he) is described by a classical Cramér-Lundberg (C-L) model. In addition to reinsurance, the insurer and the reinsurer (principal/she) are both allowed to invest their surpluses into a financial market containing one risk-free asset (e.g. a short-rate account) and one risky asset (e.g. a market index). In this paper, the insurer and the reinsurer are ambiguity averse and have specific modeling risk aversion preferences for the insurance claims (this relates to the jump term in the stochastic models) and the financial market's risk (this encompasses the models' diffusion term). The reinsurer designs a reinsurance contract that maximizes the exponential utility of her terminal wealth under a worst-case scenario which depends on the retention level of the insurer. By employing the dynamic programming approach, we derive the optimal robust reinsurance contract, and the value functions for the reinsurer and the insurer under this contract. In order to provide a more explicit reinsurance contract and to facilitate our quantitative analysis, we discuss the case when the claims follow an exponential distribution; it is then possible to show explicitly the impact of ambiguity aversion on the optimal reinsurance.     

Optimal investment-reinsurance with dynamic risk constraint and regime switching

We study an optimal investment–reinsurance problem for an insurer who faces dynamic risk constraint in a Markovian regime-switching environment. The goal of the insurer is to maximize the expected utility of terminal wealth. Here the dynamic risk constraint is described by the maximal conditional Value at Risk over different economic states. The rationale is to provide a prudent investment–reinsurance strategy by taking into account the worst case scenario over different economic states. Using the dynamic programming approach, we obtain an analytical solution of the problem when the insurance business is modeled by either the classical Cramer–Lundberg model or its diffusion approximation. We document some important qualitative behaviors of the optimal investment–reinsurance strategies and investigate the impacts of switching regimes and risk constraint on the optimal strategies.     

适配农村城镇化进程的最优金融结构理论研究．

一个实体经济体的最适配金融结构,内生决定于该实体经济的禀赋特性。从经济结构内涵而论,劳动力就业结构的转换、农村要素禀赋的提升以及产业结构的调整,构成农村城镇化的重要禀赋特性,小企业和新创办企业是农村城镇化中经济结构调整的主要动力。从金融交易特征观察,农村城镇化聚集了众多小企业成长所引致的异质性融资需求,与之相关的金融契约,有别于现行的二元金融系统,其资金需求规模小,企业家风险突出,这决定了适配农村城镇化的金融制度,不可能在现有二元金融系统中单独依靠对某种金融机构的改造而确立。为加速农村城镇化进程,有必要建构“区域性”的“政策导引的商业金融系统”,其核心价值在于对小额信贷的风险甄别功能。     

存在道德风险的医院等级选择与最优公共医疗保险合同

通过构造一个医疗服务系统的均衡模型,分析了医院等级、居民道德风险与最优公共医疗保险合同之间的关系。研究表明只存在公共医疗保险体系时,如果政府部门之间缺乏协调机制,各自为政,中国的公共医疗保险支付方式将不能实现社会最优并消除道德风险;公共医疗保险合同可能引起社会福利的损失或引致道德风险。政府应该完善医院评价系统,对不同医院的水平给予准确的评级,特别是要建立起政府各部门之间的协调机制;理顺医疗服务价格体系;鼓励更多市场参与主体进入医疗保险领域,建立合理的疾病风险分担机制。     

银行业结构对产业结构升级的影响研究——基于最优金融结构理论与门槛模型的分析

基于"最优金融结构"理论,利用我国2004—2017年31个省区市的省级非平衡面板数据,实证检验了银行结构对产业结构升级的影响。结果表明:中小银行占比的增加对我国产业结构升级具有显著促进作用,且该作用在东中西部地区存在明显差异,东部地区中小银行占比增加对产业结构升级的影响并不显著,而中西部地区则具有显著的促进作用。在此基础上,运用面板门槛模型对区域差异性的影响因素进行分析,研究发现,在外商投资水平、财政收入水平、市场化水平、自然资源水平以及人力资源水平因素的不同门槛值区间内,中小银行占比增加对产业结构升级的影响具有程度和方向上的显著差异。