半马氏生灭过程

本文提出了半马氏生灭过程的概念，引进了其数字特征，并讨论了向下和向上的积分型随机泛函、遍历性及平稳分布．     

广生灭马氏链(Ⅱ)

本文在文献[1]的基础上继续讨论了广生灭马氏链,求出了向下的首达时间分布及各级矩,给出了广生灭马氏链遍历的充分必要条件以及平均反回时间的计算公式,并且在遍历的条件下,求出了其平稳分布     

广生马灭马氏链（Ⅱ）

本文在文献[1]的基础上继续讨论了广生灭马氏链,求出了向下的首达时间分布及各级矩,给出了广生灭马氏链遍历的充分必要条件以及平均反回时间的计算公式,并且在遍历的条件下,求出了其平稳分布。     

生灭型半马氏骨架过程

本文首先引进了生灭型半马氏骨架过程的定义,求出了两骨架时跳跃点τn-1(ω)与τn(ω)之间的嵌入过程X(n)(t,ω)的初始分布及寿命分布.得到了生灭型半马氏骨架过程的一维分布.其次引进了生灭型半马氏骨架过程的数字特征并讨论了它们的概率意义及相互关系.讨论了生灭型半马氏骨架过程的向上和向下的积分型随机泛函.最后讨论了它的遍历性及平稳分布,求出了平均首达时间及平均返回时间.得到了常返和正常返的充分必要条件,求出了在正常返的条件下的平稳分布.     

随机生灭Q矩阵的极限谱分布

本文主要研究随机生灭Q矩阵的极限谱分布.在严平稳遍历的情形下,本文证明随机生灭Q矩阵的经验谱分布弱收敛于某个非随机概率分布.进一步,在非严平稳遍历情形下,本文研究了比BetaHermite系综更广的一类随机矩阵模型,建立了与之相应的随机生灭Q矩阵的极限谱分布存在性,并且证明它的极限谱分布具有卷积表达式.特别地,Beta-Hermite系综所对应的随机生灭Q矩阵的极限谱分布是经典半圆率与Dirac测度δ-2的卷积.     

布朗生灭过程及股票价格模型

本文明确地给出了一类布朗生灭过程的定义,讨论了其一维分布、积分泛函的分布和矩, 得到了递推计算公式,然后讨论了布朗生灭过程对股价模型的应用.     

半马氏过程的积分型随机泛函

本文讨论了半马氏过程的积分型随机泛函,求出了“首达”时间的积分型随机泛函公式,并讨论了半马氏过程“正则性”条件,得到了飞跃点积分型随机泛函的两个0—1律     

拟生灭过程几种遍历性的判别准则(Ⅱ)

本文是文[7]的继续,研究了连续时间拟生灭过程,给出了一类连续时间拟生灭过程l-遍历和几何遍历行之有效的判别准则,并证明其不可能是多项式一致遍历和强遍历的.     

拟生灭过程几种遍历性的判别准则(Ⅱ)

本文是文[7]的继续,研究了连续时间拟生灭过程,给出了一类连续时间拟生灭过程l-遍历和几何遍历行之有效的判别准则,并证明其不可能是多项式一致遍历和强遍历的.     

一般形式的连续时间拟生灭过程各种遍历性判定准则

侯振挺、李晓花在 [1]已经讨论了具有某些特殊形式的拟生灭过程各种遍历性 ,我们将在此基础讨论一般形式连续时间拟生灭过程各种遍历性 ,并给出 [1]中连续时间拟生灭过程的指数遍历及多项式遍历的一个新证明 ,该证明给出了具有某些特殊条件下连续时间拟生灭过程遍历性与离散时间拟生灭过程遍历性之间关系 .     

Ergodicity of Quasi-birth and Death Processes （Ⅰ）

Quasi-birth and death processes with block tridiagonal matrices find many applications in various areas. Neuts gave the necessary and sufficient conditions for the ordinary ergodicity and found an expression of the stationary distribution for a class of quasi-birth and death processes. In this paper we obtain the explicit necessary and sufficient conditions for/-ergodicity and geometric ergodicity for the class of quasi-birth and death processes, and prove that they are not strongly ergodic. Keywords ergodicity, quasi-birth and death process.     

Functional inequalities for transient birth-death processes and their applications

We give a new diagram about uniform decay, empty essential spectrum and various functional inequalities, including Poincaré inequalities, super- and weak-Poincaré inequalities, for transient birth-death processes. This diagram is completely opposite to that in ergodic situation, and substantially points out the difference between transient birth-death processes and recurrent ones. The criterion for the empty essential spectrum is achieved. Some matching sufficient and necessary conditions for weak-Poincaré inequalities and super-Poincaré inequalities are also presented.     

Birth-death processes on trees

In this paper, we consider birth-death processes on a tree T and we are interested when it is regular, recurrent and ergodic (strongly, exponentially). By constructing two corresponding birth death processes on Z+, we obtain computable conditions sufficient or necessary for that (in many cases, these two conditions coincide). With the help of these constructions, we give explicit upper and lower bounds for the Dirichlet eigenvalue λ0. At last, some examples are investigated to justify our results.     

Multiple stochastic integrals constructed by special expansions of products of the integrating stochastic processes

The paper deals with problems of constructing multiple stochastic integrals in the case when the product of increments of the integrating stochastic process admits an expansion as a finite sum of series with random coefficients. This expansion was obtained for a sufficiently wide class including centered Gaussian processes. In the paper, some necessary and sufficient conditions are obtained for the existence of multiple stochastic integrals defined by an expansion of the product of Wiener processes. It was obtained a recurrent representation for the Wiener stochastic integral as an analog of the Hu–Meyer formula.     

Asymptotic behavior of posterior distributions for random processes under incorrect models

In this paper, the asymptotic behavior of posterior distributions on parameters contained in random processes is examined when the specified model for the densities is not necessarily correct. Uniform convergence of likelihood functions in some way is shown to be a sufficient condition for the posterior distributions to be asymptotically confined to a set (Theorem 1). For ergodic stationary Markov processes uniform convergence of likelihood functions is established by the ergodic theorem for Banach-valued stationary processes (Proposition 1). A sufficient condition for the uniform convergence is also shown for general random processes (Proposition 2). These results are used to analyze the asymptotic behavior of posterior distributions on parameters contained in linear systems under incorrect models (Example 1 and 2).     

Geometric ergodicity for classes of homogeneous Markov chains

The paper deals with non asymptotic computable bounds for the geometric convergence rate of homogeneous ergodic Markov processes. Some sufficient conditions are stated for simultaneous geometric ergodicity of Markov chain classes. This property is applied to nonparametric estimation in ergodic diffusion processes.     

A continuous model for non-closed graded systems and its asymptotic character

The Purpose of the paper is to study the behavior and the asymptotic character of a continuous model for non-closed graded systems. Mathematically, the model is described by a system of volterra integral equations. Then by applying known methods based on the theory of the resolvent kernel and limiting equations we analyze the behavior and the limiting structure of system. Finally, we provide necessary and sufficient conditions for the system to be weakly ergodic     

On the strong law of large numbers for sequences stationary in the narrow sense

In his recent paper published in Vestnik St. Petersburg University, Ser. Mathematics, V.V. Petrov found new sufficient conditions for the fulfillment of the strong law of large numbers for sequences of random variables stationary in the broad sense. These conditions are expressed in terms of second moments. In this paper, by using the ergodic theorem, similar problems are solved for sequences of random variables stationary in the narrow sense. In the absence of second moments, the statements of conditions involve the truncated second moments of truncated random variables. At the end of the paper, an example of a stationary sequence of random variables which is not ergodic but obeys the strong law of large numbers is given.     

Hitting Time Distributions for Denumerable Birth and Death Processes

For an ergodic continuous-time birth and death process on the nonnegative integers, a well-known theorem states that the hitting time T _0,n starting from state 0 to state n has the same distribution as the sum of n independent exponential random variables. Firstly, we generalize this theorem to an absorbing birth and death process (say, with state ?1 absorbing) to derive the distribution of T _0,n . We then give explicit formulas for Laplace transforms of hitting times between any two states for an ergodic or absorbing birth and death process. Secondly, these results are all extended to birth and death processes on the nonnegative integers with ?? an exit, entrance, or regular boundary. Finally, we apply these formulas to fastest strong stationary times for strongly ergodic birth and death processes.     

具有标准发生率的随机SIR传染病模型的建立及平稳分布与疾病灭绝研究

研究了一类具有标准发生率以及考虑随机扰动与系统变量成正比的随机SIR传染病模型.首先,对于任意的正的初值,系统存在唯一的全局正解以及通过构造合适的随机李雅普诺夫函数,得到了模型遍历平稳分布存在的充分条件.其次,给出了疾病灭绝的充分条件,并与模型遍历平稳分布存在的充分条件作对比,得出了在特定条件下随机SIR模型的阈值.最后通过数值模拟验证了结果的正确性.