A MULTINOMIAL APPROXIMATION FOR AMERICAN OPTION PRICES IN LÉVY PROCESS MODELS

This paper gives a tree-based method for pricing American options in models where the stock price follows a general exponential Lévy process. A multinomial model for approximating the stock price process, which can be viewed as generalizing the binomial model of Cox, Ross, and Rubinstein (1979) for geometric Brownian motion, is developed. Under mild conditions, it is proved that the stock price process and the prices of American-type options on the stock, calculated from the multinomial model, converge to the corresponding prices under the continuous time Lévy process model. Explicit illustrations are given for the variance gamma model and the normal inverse Gaussian process when the option is an American put, but the procedure is applicable to a much wider class of derivatives including some path-dependent options. Our approach overcomes some practical difficulties that have previously been encountered when the Lévy process has infinite activity.     

Stability and Segregation in Group Formation

This paper presents a model of group formation based on the assumption that individuals prefer to associate with people similar to them. It is shown that, in general, if the number of groups that can be formed is bounded, then a stable partition of the society into groups may not exist. (A partition is defined as stable if none of the individuals would prefer be in a different group than the one he is in.) However, if individuals' characteristics are one-dimensional, then a stable partition always exists. We give sufficient conditions for stable partitions to be segregating (in the sense that, for example, low-characteristic individuals are in one group and high-characteristic ones are in another) and Pareto efficient. In addition, we propose a dynamic model of individual myopic behavior describing the evolution of group formation to an eventual stable, segregating, and Pareto efficient partition. Journal of Economic Literature Classification Numbers: C72, H41.     

THE JOINT ARRIVAL AND DEPARTURE PROCESS FOR THE M/M/l QUEUE

We consider the M/M/1-queue and derive an explicit expression for the joint distribution of the number of arrivals and the number of departures in [0, t), given the number of customers initially present. The derivation is almost purely combinatorial, it avoids the use of generating functions, and immediately yields a simple probabilistic interpretation of the result.     

转型背景下的社会心理优化

社会转型带来的一项艰巨工作就是解决人们的不良社会心理问题.如何从理论上探索优化社会心理的方法.这是当前构建和谐辽宁急需解决的理论问题.通过对辽宁地区不良社会心理的特点、不良社会心理的形成原因与机制的解析,提出优化社会心理要发挥舆论导向、营造社会公正公平环境、切实解决民生问题、建立有效心理疏导机制、不断提高科学思维能力等心理疏导路径.     

农民工社会认同的形成——基于建筑业农民工的考察

农民工的社会认同关系到这个群体城市融入的问题。依据对建筑业农民工群体实地考察和问卷调查,探讨社会结构和制度安排如何建构了农民工群体的归属感问题。对社会认同的研究不仅要关注宏观制度结构因素对群体的身份地位的作用和影响,还应从微观的角度,分析制度设置是如何建构成员对群体的依附、归属并建构出群体边界的问题。只有改善农民工的劳动条件,提高他们的保障水平,这个群体才有可能融入城市。     

基于模糊层次的商标价值评估方法研究

基于商标价值的时效性、不确定性和模糊性等特征,本文分析了影响商标价值的主要因素,在此基础上构建商标价值评估指标体系,应用层次分析法计算各指标的权重,再尝试将模糊综合评价法应用于商标价值评估,以期为企业商标价值评估提供一种新思路。     

基于模糊层次分析法和聚类分析的突发事件分级研究

针对传统的突发事件分级缺乏对灾害事件救援和治理过程中的动态分析,难以准确的量化分级,难以为实际的工作提供科学的指导等问题。本文以某地区旱灾为例,采用模糊层次分析法结合聚类分析对突发事件进行分级,它能够有效整合专家共识,满足突发事件分级的要求和体现突发事件分级中的动态性。     

化工行业循环经济评价指标体系建立及应用研究

化工产业是循环经济建设的重点,循环经济评价指标体系建设是一项重要的工作。在已有的研究成果基础上,建立可以量化评价的化工行业循环经济评价指标体系,运用层次分析法,给出该指标体系的权重,通过案例分析,验证了其合理性。