�η��������˶������ֲ�ʱ�Ĺ⻬��

Let, be two independent,
-dimensional sub-fractional Brownian motions with respective indices.
Assume. Our principal results are the necessary and sufficient condition for the
existence and smoothness of the collision local time and the intersection local time of
and through chaos expansion and elementary inequalities.     

ָ��-٤��ģ�������ռ�ֵ�����ı�Ҷ˹����

VaR风险度量在金融、保险中有重要的应用. 本文建立了贝叶斯模型, 在某种损失函数下研究了VaR风险度量的贝叶斯估计. 证明了指数-伽马分布下贝叶斯估计的强相合性和渐近正态性, 最后利用数值模拟的方法验证了不同样本容量下估计的收敛速度.     

���ڳ�����α�������������ĺ�ѡ�����ݿ����������ƶ��о�

??How to solve the inference problem of candidate database web surveys is an urgent problem to be solved in the development of web survey. In order to solve this problem, the inference method of non-probability sampling based on superpopulation pseudo design and the combined sample is proposed. A superpopulation model is firstly built up to construct pseudo weights for a survey sample of the web candidate database. The estimator of the population mean is then computed according to the combined sample composed of the survey sample of the web candidate database and a probability sample. The variance estimator of the population mean estimator is lastly derived according to the variance estimation theory of the superpopulation model. The Bootstrap and Jackknife methods are also used to compute the variance estimator. And all these variance estimation methods are compared. The research results show that the population mean estimator based on superpopulation pseudo design and the combined sample is better, and has higher efficiency than the estimator only using the probability sample and the weighted estimator only using the survey sample of the web candidate database. The variance estimator computed by using the VM1, VM2 and VM3 method are relatively better.     

SAHARAЧ�ú����µı����˵�����Ͷ�ʲ���

??In this paper, we consider the optimal investment strategy which maximizes the utility of the terminal wealth of an insurer with SAHARA utility functions. This class of utility functions has non-monotone absolute risk aversion, which is more flexible than the CARA and CRRA utility functions. In the case that the risk process is modeled as a Brownian motion and the stock process is modeled as a geometric Brownian motion, we get the closed-form solutions for our problem by the martingale method for both the constant threshold and when the threshold evolves dynamically according to a specific process. Finally, we show that the optimal strategy is state-dependent.     

����������֦�����˶���quenched�����µ����ļ��޶���

We establish a quenched central limit theorem (CLT) for the branching Brownian motion with random immigration in dimension $d\geq4$. The limit is a Gaussian random measure, which is the same as the annealed central limit theorem, but the covariance kernel of the limit is different from that in the annealed sense when d=4.     

�������������϶����Ⱥ˵ĸ߽׵�������

Let p_M(t,x,y) be the minimal heat kernel of a d-dimenional compact Riemannian manifold M for any time t\in(0,1] and x,y\in M. Using the horizontal Brown bridge on M, we prove that, for any nonnegative integers n and m, there is a constant C depending on n,m and the manifold M, such that |\nabla^n_x\nabla^m_y\ln p_M(t,x,y)|\leq C[d(x,y)/t+1/\sqrt{t}\,]^{n+m}$, which generalizes the conclusion of the higher derivatives of the logarithmic heat kernel \ln p_M(t,x,y) about single variable in \ncite{1}.     

����Լ���������������MinimaxԤ��

本文研究了独立随机变量之和的绝对矩的几个性质, 其中包括$\ep|X+Y|-\ep|X-Y|$的表达式, 这里$X$和$Y$是相互独立的随机变量.     

���ն����ı�Ҷ˹���Ƽ���ͳ�Ʒ���

??The Bayesian model are established for the VaR and related risk measurements. The relationship between VaR and other risk measurements including expect shortfall, tail condition expectation and conditional value at risk are discussed. Furthermore, the Bayesian estimates and Bayesian predictors of these risk measurement are derived. Thirdly, the consistency and asymptotic normality in the exponential risk model are proved. Finally, the numerical simulation method is used to verify the convergence rate under different sample sizes.     

һ�������Ȩ�͵Ľ����Լ���Ӧ��

This paper considers the asymptotics of randomly weighted sums and their maxima, where the increments {X_i,i\geq1\} is a sequence of independent, identically distributed and real-valued random variables and the weights {\theta_i,i\geq1\} form another sequence of non-negative and independent random variables, and the two sequences of random variables follow some dependence structures. When the common distribution F of the increments belongs to dominant variation class, we obtain some weakly asymptotic estimations for the tail probability of randomly weighted sums and their maxima. In particular, when the F belongs to consistent variation class, some asymptotic formulas is presented. Finally, these results are applied to the asymptotic estimation for the ruin probability.     

�ɿɼӷ��������˶����������������ƫ΢�ַ����м�����Ȼ����������ƫ��ԭ��

In this article, using the limit theory of martingales, we study the moderate deviation for maximum likelihood estimator of unknown parameter in the stochastic partial differential equation driven by additive fractional Brownian motion with Hurst parameter, and the rate function can be calculated. Moreover, we apply our main result to several examples.     

混合分数布朗运动环境下欧式期权定价

假设股票价格变化过程服从混合分数布朗运动,建立了混合分数布朗环境下支付连续红利的欧式股票期权的定价模型.利用混合分数布朗运动的It-公式,将支付连续红利的欧式股票期权的定价问题转化为一个偏微分方程,通过偏微分方程求解获得了混合分数布朗运动环境下支付连续红利的欧式股票看涨期权的定价公式.     

分形布朗运动下有交易成本的外汇期权定价

研究了有交易成本的分形Black-Scholes外汇期权定价问题.基于汇率的分形布朗运动分布假设,运用分形布朗运动的性质和随机微积分方法,得到了欧式外汇期权价格所满足的偏微分方程.最后,建立离散时间条件下的非线性期权定价模型,并且通过解期权价格的偏微分方程给出了有交易成本的欧式外汇期权定价公式.     

分数布朗运动和泊松过程共同驱动下的择好期权定价

本文讨论两资产择好期权的定价问题。在风险中性假设下,建立了两资产价格过程遵循分数布朗运动和带非时齐Poisson跳跃—扩散过程的择好期权定价模型,应用期权的保险精算法,给出了相应的择好期权的定价公式。     

混合分数布朗运动环境下欧式障碍期权定价

当股票价格遵循混合分数布朗运动时,利用Δ-对冲和混合分数It8公式,建立混合分数布朗运动下欧式障碍期权定价模型,通过换元法将期权定价的偏微分方程转化为热传导方程,求得显示解.在此基础上,得到欧式障碍期权看涨-看跌平价关系式.由此,再根据敲入-敲出障碍期权关系式可推出障碍期权所有类型的定价公式.     

分数布朗运动下欧式复杂任选期权定价

在分数布朗运动环境下,利用拟鞅定价的方法,给出欧式复杂任选期权的定价公式,并用数值方法分析了选择日和Hurst参数与期权价格的关系。     

鞅分析在具有红利支付的n次幂型欧式期权定价中的应用

本文探讨了鞅分析在具有红利支付的n次幂型欧式期权定价中的应用,即用鞅分析的技巧与方法研究了在标的资产服从分数布朗运动的条件下具有红利支付的n次幂型欧式期权定价问题,并获得了其公式。丰富了已有期权定价结果,使期权定价公式更有利于实际的应用。     

分数布朗运动下几何平均亚式权证的定价

假设股票价格变化过程服从几何分数布朗运动,建立了分数布朗运动下的亚式期权定价模型.利用分数-It-公式,推导出分数布朗运动下亚式期权的价值所满足的含有三个变量偏微分方程.然后,引进适当的组合变量,将其定解问题转化为一个与路径无关的一维微分方程问题.进一步通过随机偏微分方程方法求解出分数布朗运动下亚式期权的定价公式.最后利用权证定价原理对稀释效用做出调整后,得到分数布朗运动下亚式股本权证定价公式.<正>~~     

次分数布朗运动下可分离交易可转债的定价及其风险参数

科学合理的定价是可分离交易可转债交易的基础.考虑到金融资产价格序列的长记忆性,应用次分数布朗运动的It?公式和无风险套利原理,建立标的资产支付连续红利且资产价格遵循几何次分数布朗运动的可分离交易可转债定价模型.并利用Mellin变换求解得到定价模型的解析解.最后,分析几个风险参数对可分离交易可转债价值的影响,并通过数值...     

����ʱ��任�ͷ����͹����µ���Ȩ���ۼ�ģ�����

??Model of option pricing driven by Brownian motion is the most classical model. However, it can not describe long-term property and invariance in a short period of time of asset price. In this article, option pricing model driven by sub-fractional Brownian motion is studied under time-transform with dividend-paying. Firstly, the model of diffusion B-S model of sub-fractional Brownian motion is build, and get option pricing formula with dividends. Secondly, statistical simulation is used by real data in finance and show that new model can reflect real financial assets.     

连续红利支付在跳扩散模型下的再装期权的定价

本文在连续时间支付红利,且股票价格服从Poisson跳-扩散过程的假设下,建立股票价格模型,并应用保险精算法给出一类奇异期权—再装期权再装一次情况下的定价公式.