依生灭过程索赔两险种风险模型

本文建立了依生灭过程索赔的两险种风险模型,主要对该模型的破产概率进行了研究,并给出了关于条件破产概率序列的微分积分方程以及破产概率收敛速率的上界,这类似于Cramer-Lundberg逼近,其逼近程度虽然不如Cramer-Lundberg逼近"精确",但不要求索赔额分布是尾指数的.     

重尾索赔下带干扰风险模型破产概率的等价式

Embrechts—Goldie-Veraverbeke公式给出了在重尾索赔Cramer-Lundberg风险模型下关于破产概率的等价式．本文将上述风险模型推广到带干扰的Cramer-Lundberg风险模型,研究了索赔分布时破产概率的等价关系式．     

相依索赔Poisson风险模型的Cramer-Lundberg逼近(英文)

本文考虑一类具有相依索赔的Poisson风险模型.利用无穷小方法,得到了破产概率的Cramer-Lundberg逼近及其精确表达式.     

变利率风险模型下破产概率的渐近估计

本文考虑变利率的离散时间风险模型的破产概率．在个体净损失服从ERV族和DnL族时,分别得到了有限时间和无限时间破产概率的渐近估计及上下界表达式,并利用matlab软件对有限时间破产概率的下界进行了数值模拟．     

跳-扩散风险模型的最优投资策略和破产概率研究

对盈余投资于金融市场的跳-扩散风险模型的最优投资策略和破产概率进行了研究,得到最优投资策略和最小破产概率的显示解,发现破产概率满足Lundberg等式．最后通过数值计算,得到最小破产概率与无风险利率,投资和相关系数之间的关系,以及无风险利率和相关系数对最优投资策略的影响．     

带利率的更新风险模型的破产概率的上界估计

本研究了在常利率条件下普通更新风险模型的破产概率问题．采用一种递推的方法给出了这种情况下破产概率的一个上界估计．     

完全离散的经典风险模型

本文系统地探讨了完全离散的经典风险模型，特别是重点研究了与风险有关的最终破产概率，破产前一刻的盈余和破产时赤字的概率律．Gerber仅在初始盈余为零的情况下给出了上述概率律的显式解，本文则对任意的初始盈余u≥0，给出了上述概率或概率律的递推解、变换解与显式解．     

经典风险模型中破产概率的一个渐近式

本文研究经典风险模型中破产概率的渐近行为．利用几何和的方法，获得了索赔额的分布属于S（γ）．γ〉0。时破产概率的一个局部渐近式．同时．给出了一个具体的数值的例子．     

离散的三项分布风险模型

本文探讨了离散的三项分布风险模型，重点研究了与风险有关的最终破产概率和破产前一刻的盈余的概率律．本文对任意的初始盈余u≥0，给出了上述概率或概率律的递推公式，变换公式和显式公式．其结果可以在离散的多项分布风险模型中得到推广．     

带干扰的Erlang(2)风险模型的不破产概率

本文讨论了带干扰的Erlang(2)风险模型,通过构造一个延迟更新过程,我们得到了不破产概率满足的积分-微分方程,进而得到了不破产概率的明确表达式．     

Local asymptotic behavior of the survival probability of the equilibrium renewal model with heavy tails

Recently, Tang established a local asymptotic relation for the ruin probability in the Cramer-Lundberg risk model. In this short note we extend the corresponding result to the equilibrium renewal risk model.     

更新风险模型破产赤字概率的上界

本文给出了更新风险模型破产赤字上界的一种算法,这种算法通过引入一个单调积分算子,得到了比Cramer-Lundberg上界更好的一些结果。     

变保费率扰动风险模型的有限时间破产概率和大偏差

该文考虑变保费率的扰动风险模型, 其中索赔的分布是重尾的. 对这个风险模型, 给出了索赔剩余过程的精细大偏差; 同时, 还得到了它的有限时间破产概率的Cramer-Lundberg型极限结果.     

保险联结风险投资模型的赤字问题

保险公司被允许将部分资金投入风险市场,这样保险公司经营的风险来自于未来实际发生索赔的不确定性和投资收益的不确定性。研究了由经典的Cramer-Lundberg模型与按照几何布朗运动股票价格变动的一个风险模型,获得了三种资产分配情况下股票价格波动对赤字发生概率下界的影响。     

基于Hamilton-Jacobi-Bellman方程求解保险业最优投资策略

在经典复合泊松模型中,保险公司将资金投入一个风险投资过程和一个无风险投资过程.当索赔的分布确定后,运用随机控制中的HJB方程最小化保险公司的破产概率,在已知投资规模或投资组合的情况下求解二者中的另一项,进而得到最优投资策略并讨论各种策略的运用对破产概率的影响.解决保险公司的投资资金分配问题,在实际应用中具有一定的参考价值.     

Singular boundary value problem for the integrodifferential equation in an insurance model with stochastic premiums: Analysis and numerical solution

A singular boundary value problem for a second-order linear integrodifferential equation with Volterra and non-Volterra integral operators is formulated and analyzed. The equation is defined on ?₊, has a weak singularity at zero and a strong singularity at infinity, and depends on several positive parameters. Under natural constraints on the coefficients of the equation, existence and uniqueness theorems for this problem with given limit boundary conditions at singular points are proved, asymptotic representations of the solution are given, and an algorithm for its numerical determination is described. Numerical computations are performed and their interpretation is given. The problem arises in the study of the survival probability of an insurance company over infinite time (as a function of its initial surplus) in a dynamic insurance model that is a modification of the classical Cramer-Lundberg model with a stochastic process rate of premium under a certain investment strategy in the financial market. A comparative analysis of the results with those produced by the model with deterministic premiums is given.     

Star-shaped approximation approach for stochastic programming problems with probability function

Star-shaped probability function approximation is suggested. Conditions of log-concavity and differentiability of approximation function are obtained. The method for constructing stochastic estimates of approximation function gradient and stochastic quasi-gradient algorithm for probability function maximization are described in the paper     

Saddlepoint Approximations to the Probability of Ruin in Finite Time for the Compound Poisson Risk Process Perturbed by Diffusion

A large deviations type approximation to the probability of ruin within a finite time for the compound Poisson risk process perturbed by diffusion is derived. This approximation is based on the saddlepoint method and generalizes the approximation for the non-perturbed risk process by Barndorff-Nielsen and Schmidli (Scand Actuar J 1995(2):169–186, 1995). An importance sampling approximation to this probability of ruin is also provided. Numerical illustrations assess the accuracy of the saddlepoint approximation using importance sampling as a benchmark. The relative deviations between saddlepoint approximation and importance sampling are very small, even for extremely small probabilities of ruin. The saddlepoint approximation is however substantially faster to compute.     

Continuous approximation schemes for stochastic programs

One of the main methods for solving stochastic programs is approximation by discretizing the probability distribution. However, discretization may lose differentiability of expectational functionals. The complexity of discrete approximation schemes also increases exponentially as the dimension of the random vector increases. On the other hand, stochastic methods can solve stochastic programs with larger dimensions but their convergence is in the sense of probability one. In this paper, we study the differentiability property of stochastic two-stage programs and discuss continuous approximation methods for stochastic programs. We present several ways to calculate and estimate this derivative. We then design several continuous approximation schemes and study their convergence behavior and implementation. The methods include several types of truncation approximation, lower dimensional approximation and limited basis approximation.His work is supported by Office of Naval Research Grant N0014-86-K-0628 and the National Science Foundation under Grant ECS-8815101 and DDM-9215921.His work is supported by the Australian Research Council.