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.     

高等职业院校实践学分制的思考

高等职业院校实施学分制是教育教学改革的必然趋势,因此,高等职业院校要勇于实践,不断探索。文章就高等职业院校如何实践学分制,提出了从制订学分制的政策、学分制的操作流程到建立学分制管理手段的一些建议。     

强化政府引导服务功能 提高企业整体创新能力

怀化是一个欠发达的山区,要发展、壮大民营经济,提升民营科技企业整体创新能力,必须注重发挥科技部门职能作用,强化政府引导服务功能。     

Regulating Banks through Market Discipline: A Survey of the Issues

Abstract.  The interest in the application of market discipline to regulate the financial industry has boomed recently due to the proposed New Capital Accord. This paper reviews the potential role market discipline can play in financial regulation. We start with a discussion of the rationale for financial regulation and with a brief history of the current regulatory mechanisms. Next, a definition of market discipline as a regulatory mechanism is advanced. We evaluate the disciplining power various market participants have. Finally, we argue that more external risk management disclosure is a condition sine qua non in order to enable market discipline as a regulatory mechanism. In this respect, the Basle Committee has taken the right approach.     

A comparison of several approximations to the power function of the likelihood ratio test in covariance structure analysis*

In this paper we compare alternative asymptotic approximations to the power of the likelihood ratio test used in covariance structure analysis for testing the fit of a model. Alternative expressions for the noncentrality parameter (ncp) lead to different approximations to the power function. It appears that for alternative covariance matrices close to the null hypothesis, the alternative ncp's lead to similar values, while for alternative covariance matrices far from H_o the different expressions for the ncp can conflict substantively. Monte Carlo evidence shows that the ncp proposed in Satorra and Saris (1985) gives the most accurate power approximations.     

系统评估过程研究

通过系统及其目标的定义、议题及其目标的确立、指标及其性能标准的选择、指标的测量及其图形的绘制、指标的聚合、绘制指标图并评估其结果等步骤,构建系统评估过程模型,并以区域可持续发展系统为例,进行区域可持续发展评估。     

积分循环赛在学校篮球竞赛中的应用研究

为了在学校篮球竞赛中引入积分循环赛，文章针对棋类积分编排存在的三个方面问题，通过采用每轮比赛排名作为配对排序的条件，并对棋类积分编排方法进行了一定的简化移植，经过多次试验性编排，运用电子表格技术设计出了一整套篮球积分编排方法。这种方法可实际运用于篮球积分循环赛的手工编排，并能为实现计算机篮球积分编排提供理论依据。     

深圳中心商务区的区位转移及其机制

20世纪80年代形成的罗湖商业区可以看作是深圳目前的中心商务区，正在建设中的深圳中心区（福田中心区）将会是未来深圳的中心商务区。在深圳城市经济重心西移等内外固定的作用下，深圳商务中心区西移趋势已经形成。本文主要就福田中心区的成长和深圳中心商务区由罗湖向福田转移的机制作了探讨。     

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.     

国有企业融资次序的政治经济学分析

与经典资本结构理论的结论不同，我国国有企业的融资次序恰好是倒序的。这一现象有着深刻的政治经济学内涵，本质上它是由国家追求义理性的最大化，缓解财政压力的行为所内生决定的。因此，单纯从西方主流理论出发，不考虑我国转轨经济的背景对国有企业融资行为和由此而引致的治理结构所进行的分析，是不得要领的。