基于不对称需求信息的数量折扣设计

通过建立数量折扣设计优化模型,利用委托代理理论分别分析了完全和不完全需求信息条件下,商品供应商如何为一群异质的零售商制定价格政策,实现其中望利润的最大化.在完全需求信息条件下,单一价格就能使供应商实现利润最大化;而在需求信息为不对称条件下,逆向选择使单一价格失效,此时,数量折扣是一种能够有效增加零售商订货量的激励方式.     

不完全市场下考虑损失厌恶的连续时间投资组合选择

在不完全市场条件下研究了一般情形下的损失厌恶投资者的连续时间投资组合选择模型. 面对市场风险, 投资者的偏好由一个S-型的价值函数定义. 通过把不完全市场转换为完全市场, 利用鞅方法和复制技术, 分别获得了投资者的最优期末财富以及最优投资策略. 最后讨论了一个分段幂函数的例子, 在模型系数为确定的常数情形下, 得到了最优解的显示表达式.     

不完全信息随机截尾模型的MLE 的Chung 重对数律

在一定条件下,证明不完全信息随机截尾模型的MLE 满足 Chung重对数律. 作为其推论得到:不完全信息随机截尾试验下,指数分布和Weibull 分布的MLE 满足Chung 重对数律.     

企业信息不完全情况下的首次通过违约概率模型

基于Merton的结构化模型,利用几何布朗运动理论建立了不完全信息条件下的企业首次通过违约概率模型.根据企业的财务报表及信用记录,提出了一种新的不完全信息假设;在模型上引入股票的流通性价值,并改进其基于Merton模型的度量方法,使其适用于首次通过模型并求得内生违约边界,利用此边界给出了不完全信息条件下的企业违约概率,并分析了股票流通价值和股价与企业资产的相关关系对违约概率的影响.     

不完全成本信息下差异产品厂商古诺竞争博弈分析

在成本信息不完全条件下研究了具有替代性产品的古诺竞争问题,并对完全信息与不完全信息两种情形下的均衡结果做了比较。研究表明,在不完全信息下,产品间的替代性、成本函数的概率值以及低成本识别因子对成本信息优势厂商和劣势厂商的均衡产量大小和均衡利润高低均有影响,但对各厂商间的均衡价格高低无影响。无论上述参数如何取值,低成本厂商在不完全信息条件下的贝叶斯纳什均衡产量、均衡价格、均衡利润以及市场份额均低于完全信息条件下的纳什均衡结果;而对高成本厂商而言,结果恰好相反。     

基于税率因素的中间产品转移定价研究

在中间产品转移定价过程中引进税率因素.在中间产品价格采用成本加成定价法的条件下,分别基于下游企业对上游企业的单位成本具有完全信息和不完全信息两种情况,对厂商的中间产品定价方法进行了研究,得出具有完全信息的企业总利润大于不具有完全信息的企业总利润的结论.并在此基础上通过变化的成本加成率建立了减少上游企业提供不真实单位成本导致利润损失的模型.     

不完全博弈学习过程的虚拟行动规则

本文把博弈学习虚拟行动规则的学习时间一般化,研究不完全学习过程中参与人策略选择的收敛性及效用一致性问题. 分析结果表明：当学习时间不完全时,在学习一致到达的条件下,虚拟行动规则对严格纳什均衡是吸收的; 在学习时间充分及时与虚拟行动非频繁转换的条件下,各参与人的虚拟行动具有效用一致性.     

广义不变凸多目标半无限规划的鞍点条件

利用广义代数运算,定义了一类不变凸函数和不完全向量值Lagrange函数的鞍点,研究了涉及此类函数的多目标半无限规划问题,得到了广义鞍点的必要性和充分性条件.在更弱的凸性条件下,得到了几个重要结果.     

纯交换经济环境中的双人贝叶斯机制研究

将Dutta和Sen(1994)关于不完全信息环境中二人贝叶斯执行问题扩展到纯交换经济环境中,建立了纯交换经济的双人贝叶斯机制模型,给出当偏好关系和初始禀赋都是不完全信息环境下,一个社会选择规则贝叶斯可执行的充分条件和必要条件.     

带有不完全信息的随机截尾广义线性模型的中偏差

本文介绍了随机截尾的带有不完全信息的广义线性模型,并在一定条件下运用Taylor渐近展开方法得到了此模型的极大似然估计的中偏差.     

基于训练和过滤的期望均衡及其实现路径

期望均衡是博弈局中人或局外人对于博弈均衡点的一致期望,强调互利共赢,它要求博弈群体的每个成员对期望均衡点有一个共同的预期.显然,基于纳什均衡的帕累托优化组合策略是一个比纳什均衡更有效的期望均衡.要实现期望均衡,可采用局中人参与的训练与学习使得群体的预期一致,也可采用第三方过滤器来达到期望目标.在期望均衡的概率分布下,个体行为的偏离不能比均衡态取得更多收益.否则,训练就是无效的,第三方过滤器就是不公平的.     

Effect of herd shape in a diffusive predator-prey model with time delay

In this paper, we deal with the effect of the shape of herd behavior on the interaction between predator and prey. The model analysis was studied in three parts. The first, The analysis of the system in the absence of spatial diffusion and the time delay, where the local stability of the equilibrium states, the existence of Hopf bifurcation have been investigated. For the second part, the spatiotemporal dynamics introduce by self diffusion was determined, where the existence of Hopf bifurcation, Turing driven instability, Turing-Hopf bifurcation point have been proved. Further, the order of Hopf bifurcation points and regions of the stability of the non trivial equilibrium state was given. In the last part of the paper, we studied the delay effect on the stability of the non trivial equilibrium, where we proved that the delay can lead to the instability of interior equilibrium state, and also the existence of Hopf bifurcation. A numerical simulation was carried out to insure the theoretical results.     

A predator–prey–disease model with immune response in infected prey

In this paper, a predator–prey–disease model with immune response in the infected prey is formulated. The basic reproduction number of the within-host model is defined and it is found that there are three equilibria: extinction equilibrium, infection-free equilibrium and infection-persistent equilibrium. The stabilities of these equilibria are completely determined by the reproduction number of the within-host model. Furthermore, we define a basic reproduction number of the between-host model and two predator invasion numbers: predator invasion number in the absence of disease and predator invasion number in the presence of disease. We have predator and infection-free equilibrium, infection-free equilibrium, predator-free equilibrium and a co-existence equilibrium. We determine the local stabilities of these equilibria with conditions on the reproduction and invasion reproduction numbers. Finally, we show that the predator-free equilibrium is globally stable.     

EXISTENCE OF STABLE EQUILIBRIUM FOR A CLASS OF MULTI-SPECIES ECOSYSTEM

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Rates of mixing for potentials of summable variation

It is well known that for subshifts of finite type and equilibrium measures associated to Hölder potentials we have exponential decay of correlations. In this article we derive explicit rates of mixing for equilibrium states associated to more general potentials.

     

Threat bargaining games with a variable population

In this paper we establish links between desirable properties satisfied by familiar solutions to bargaining games with a variable population and the Nash equilibrium concept for threat bargaining games. We introduce three new concepts for equilibrium threat strategies called strategic stability, strategic monotonicity with respect to changes in the number of agents and strategic constancy. Our primary objective in this paper is to show that familiar assumptions satisfied by bargaining games with a variable population yield equilibrium threat strategies which satisfies in a very natural way the concepts we have introduced.     

Equilibrium path in oligopolistic market of nonrenewable resource

In this paper we study the oligopoly model of nonrenewable resource in which the unit production cost is variable and depends on the resource reserve level. We consider both the open-loop strategy and the closed-loop strategy of this dynamical differential game. For the case of linear cost function we have observed that the open-loop equilibrium and the self-feedback equilibrium satisfy the same equilibrium conditions, which can be described as a dynamical system. The analysis shows that the equilibrium path of the model is the stable orbit of this system, and this result leads to further studies of the properties of the total extraction and reserve and the individual ones of each producer. For the total extraction rate and reserve, some of the properties are similar to those of most oligopoly models with fixed unit production cost. For the individual behaviors, we have found out the solution expressions of the individual extraction rate and resource reserve and got the main result that the producer with larger initial stock has a larger but declining market share and the share of each producer converges toward the average one when time approaches to infinite.     

Equilibrium constrained optimization problems

We consider equilibrium constrained optimization problems, which have a general formulation that encompasses well-known models such as mathematical programs with equilibrium constraints, bilevel programs, and generalized semi-infinite programming problems. Based on the celebrated KKM lemma, we prove the existence of feasible points for the equilibrium constraints. Moreover, we analyze the topological and analytical structure of the feasible set. Alternative formulations of an equilibrium constrained optimization problem (ECOP) that are suitable for numerical purposes are also given. As an important first step for developing efficient algorithms, we provide a genericity analysis for the feasible set of a particular ECOP, for which all the functions are assumed to be linear.     

On the stability of the solution for multiobjective generalized games with the payoffs perturbed

This paper studies the stability of weakly Pareto-Nash and Pareto-Nash equilibrium for multiobjective generalized games with the payoff perturbed. Using a simple characterization of the weakly Pareto-Nash solution, we obtain a generic continuous result concerning weakly Pareto-Nash solution mapping. Examples are given to show that Pareto-Nash equilibrium mapping is neither upper semicontinuous nor lower semicontinuous. Through seeking the sub-mapping, we prove that most multiobjective generalized games have at least one essential Pareto-Nash solution.     

Instability of equilibrium points of some Lagrangian systems

In this work we show that, if L is a natural Lagrangian system such that the k-jet of the potential energy ensures it does not have a minimum at the equilibrium and such that its Hessian has rank at least n−2, then there is an asymptotic trajectory to the associated equilibrium point and so the equilibrium is unstable. This applies, in particular, to analytic potentials with a saddle point and a Hessian with at most 2 null eigenvalues.The result is proven for Lagrangians in a specific form, and we show that the class of Lagrangians we are interested can be taken into this specific form by a subtle change of spatial coordinates. We also consider the extension of this results to systems subjected to gyroscopic forces.