A Local Asymptotic Behavior for Ruin Probability in the Renewal Risk Model

Let R（t）=u＋ct-∑ I=1^N（t） Xi,t≥0 be the renewal risk model, with Fx（x）being the distribution function of the claim amount X. Let ψ（u） be the ruin probability with initial surplus u. Under the condition of Fx（x） ∈ S^＊（γ）,y ≥ 0, by the geometric sum method, we derive the local asymptotic behavior for ψ（u,u ＋ z] for every 0 （ z （ oo, On one hand, the asymptotic behavior of ψ（u） can be derived from the result obtained. On the other hand, the result of this paper can be applied to the insurance risk management of an insurance company.

Survival probability and ruin probability of a risk model

In this paper, a new risk model is studied in which the rate of premium income is regarded as a random variable, the arrival of insurance policies is a Poisson process and the process of claim occurring is p-thinning process. The integral representations of the survival probability are gotten. The explicit formula of the survival probability on the infinite interval is obtained in the special casc cxponential distribution.The Lundberg inequality and the common formula of the ruin probability are gotten in terms of some techniques from martingale theory.

Comparison of Ruin Probabilities in Compound Poisson Risk Model

Compound Poisson risk model has been simulated. It has started with exponential claim sizes. The simulations have checked for infinite ruin probabilities. An appropriate time window has been chosen to estimate and compare ruin probabilities. The infinite ruin probabilities of two-compound Poisson risk process have estimated and compared them with standard theoretical results.

DURATION OF NEGATIVE SURPLUS FOR A TWO STATE MARKOV-MODULATED RISK MODEL

We consider a continuous time risk model based on a two state Markov process, in which after an exponentially distributed time, the claim frequency changes to a different level and can change back again in the same way. We derive the Laplace transform for the first passage time to surplus zero from a given negative surplus and for the duration of negative surplus. Closed-form expressions are given in the case of exponential individual claim. Finally, numerical results are provided to show how to estimate the moments of duration of negative surplus.

On the Markov-dependent risk model with tax

In this paper we consider the Markov-dependent risk model with tax payments in which the claim occurrence, the claim amount as well as the tax rate are controlled by an irreducible discrete-time Markov chain. Systems of integro-differential equations satisfied by the expected discounted tax payments and the non-ruin probability in terms of the ruin probabilities under the Markov-dependent risk model without tax are established. The analytical solutions of the systems of integro-differential equations are also obtained by the iteration method.

A Joint Density Function in the Renewal Risk Model

In this paper, we consider a general expression for Ф（u, x, y）, the joint density function of the surplus prior to ruin and the deficit at ruin when the initial surplus is u. In the renewal risk model, this density function is expressed in terms of the corresponding density function when the initial surplus is O. In the compound Poisson risk process with phase-type claim size, we derive an explicit expression for Ф（u, x, y）. Finally, we give a numerical example to illustrate the application of these results.

Asymptotics of discounted aggregate claims for renewal risk model with risky investment

Under the assumption that the claim size is subexponentially distributed and the insurance surplus is totally invested in risky asset, a simple asymptotic relation of tail probability of discounted aggregate claims for renewal risk model within finite horizon is obtained. The result extends the corresponding conclusions of related references.

具有随机投资收益过程的风险模型有限时间破产概率的一致渐近估计

本文考虑一类利用càdlàg过程刻画保险盈余的随机投资收益,并利用二元上尾独立刻画保险索赔额之间相依结构的保险风险模型.一方面,本文提出条件(6),在此条件下得到该风险模型有限时间破产概率的一致渐近估计式.另一方面,考虑到条件(6)的普适性,本文发现很多重要的随机过程都满足条件(6),如Lévy过程,Vasicek模型,Cox-Ingersoll-Ross(CIR)模型和Heston模型.

Ruin Probabilities for a Two-Dimensional Perturbed Risk Model with Stochastic Premiums

In this paper, we consider a two-dimensional perturbed risk model with stochastic premiums and certain dependence between the two marginal surplus processes. We obtain the Lundberg-type upper bound for the infinite-time ruin probability by martingale approach, discuss how the dependence affects the obtained upper bound and give some numerical examples to illustrate our results. For the heavy-tailed claims case, we derive an explicit asymptotic estimation for the finite-time ruin probability.

Finite Time Ruin Probabilities and Large Deviations for Generalized Compound Binomial Risk Models

In this paper, we extend the classical compound binomial risk model to the case where the premium income process is based on a Poisson process, and is no longer a linear function. For this more realistic risk model, Lundberg type limiting results for the finite time ruin probabilities are derived. Asymptotic behavior of the tail probabilities of the claim surplus process is also investigated.

期望保费准则下的最优再保险策略

再保险作为“保险的保险”,是一种有效的风险管理策略.在期望保费准则下,对成数再保险、停止损失再保险及两者的混合再保险的最优化问题进行研究.利用鞅方法得到了复合泊松风险模型中的有限时间破产概率上界,并证明了在最小化有限时间破产概率上界的指标下,停止损失再保险要优于两者的混合再保险.

Ruin Probabilities in Cox Risk Models with Two Dependent Classes of Business

In this paper we consider risk processes with two classes of business in which the two claim-number processes are dependent Cox processes. We first assume that the two claim-number processes have a two-dimensional Markovian intensity. Under this assumption, we not only study the sum of the two individual risk processes but also investigate the two-dimensional risk process formed by considering the two individual processes separately. For each of the two risk processes we derive an expression for the ruin probability, and then construct an upper bound for the ruin probability. We next assume that the intensity of the two claim-number processes follows a Markov chain. In this case, we examine the ruin probability of the sum of the two individual risk processes. Specifically, a differential system for the ruin probability is derived and numerical results are obtained for exponential claim sizes.

Ruin probability of the renewal model with risky investment and large claims

The ruin probability of the renewal risk model with investment strategy for a capital market index is investigated in this paper.For claim sizes with common distribution of extended regular variation,we study the asymptotic behaviour of the ruin probability.As a corollary,we establish a simple asymptotic formula for the ruin probability for the case of Pareto-like claims.

The Finite-time Ruin Probability of a Discrete-time Risk Model with Subexponential and Dependent Insurance and Financial Risks

Consider a discrete-time risk model with insurance and financial risks in a stochastic economic environment. Assume that the insurance and financial risks form a sequence of independent and identically distributed random vectors with a generic random vector following a wide type of dependence structure. An asymptotic formula for the finite-time ruin probability with subexponential insurance risks is derived. In doing so, the subexponentiality of the product of two dependent random variables is investigated simultaneously.

Severity of Ruin in a Markov-Dependent Risk Model

We study the severity of ruin in a Markov-dependent risk model in which the claim interarrivals and claim amounts are influenced by an external Markov chain. A system of integro-differential equation of the severity of ruin, given the initial environment state, is derived. Explicit formulas for the severity of ruin are obtained when the initial surplus is zero or when all the claim amount distributions are from rational family. In the two state model, numerical illustration with exponential claim accounts are given.

Ruin probability in Sparre Andersen risk model with claim inter-arrival times distributed as Erlang

This article deals with the ruin probability in a Sparre Andersen risk process with the inter-claim times being Erlang distributed in the framework of piecewise deterministic Markov process （PDMP）. We construct an exponential martingale by virtue of the extended generator of the PDMP to change the measure. Some results are derived for the ruin probabilities, such as the general expressions for ruin probability, Lundberg bounds, CramerLundberg approximations, and finite-horizon ruin probability.

对于大额索赔的平衡更新模型的破产概率

本文研究平衡更新风险模型的破产概率ψ（x）,这里x为保险公司初始的资本金.在假定索赔额服从重尾分布的条件下,给出了当x→∞时;ψ（x）的尾等价关系,所得结果与经典的Cramer-Lundbeng模型下的结论完全一致.

投资和干扰具有随机保费的离散风险模型

在考虑具有保费且含通货膨胀等随机干扰因素的影响,同时又考虑将多余资本用于投资以提高保险公司赔付能力的基础上,对经典的风险模型进行扩展,由此建立了一个带有投资且具有随机保费率和干扰的更为实际的风险模型.对新模型的性质进行讨论,得到了其盈利过程的平稳增量性和风险过程的统计特征;对破产概率的研究,获得了最终破产概率的Lundberg不等式及其一般表达式.最后通过数值模拟阐述了破产概率上界分别随投资额、保费额和理赔额变化而变动的情况,获得了对实际运营有启发性的结论.

随机保费率下带干扰风险模型的破产概率

考虑了保险费收取率为随机变量且含随机干扰因素的风险模型,在更一般的情形下,得到了破产概率满足的一般公式和Lundberg不等式.并且,通过实例分析了破产概率与初始资本、保费额及理赔额之间的关系.

双Poisson风险模型的破产概率

对保险费收取次数和每一张保单收取保险费均为随机变量的风险模型进行了研究,讨论盈余的性质,并给出关于调节系数所满足的方程,进而得到破产概率的一般表达式以及它的一个上界。