股票市场收益率波动长记忆性的分解及实证研究

目前股票市场长记忆性检验和建模方法，不能很好地消除短期记忆的影响，针对这一问题，本文提出寻找序列的突变点，通过将序列分解为只包含长记忆性部分和不包含长记忆性部分的序列分解技术，来排除短期记忆的影响。对上证指数和深圳成分指数收益率波动的长记忆性进行实证研究发现，将序列分解以后进行长记忆性检验，不仅可以得出长记忆性检验更为精确的结论，同时可以检验序列分解过程的效果。     

中国股票市场市盈率的检验分析

市盈率高低是我国股市的关注焦点之一。本文在比较国外证券市场的市盈率之后认为我国的市盈率偏高。这种推测得到我们理论研究和模型结论的支持,我国股市市盈率由于系统风险的掩藏、股票初始发行价偏高和股市投机性等因素而呈现较高的倍数。从2004年我国股市市盈率开始下降,逐渐接近我们模型的估计值。此外,我们实证分析认为,市盈率的高低与GDP增长、股票收益波动和国有股比重等因素不存在严格的变动关系,市盈率呈现出一种随机游走的态势,市盈率不是稳定的区间值,而是一系列的动态的时间序列变量值。     

可转换债券市场价格与其基准股票市盈率关系初探

本文试图探讨可转换债券市场价格与其基准股票市盈率间的关系。从理论上分析,市盈率作为一个较易获得的市场指标,包含了上市公司增长机会(growth opportunity)的信息,反映了投资者对未来股价上升的预期。同时可转换债券的价格对其基准股票价格未来上升的可能性十分敏感,因此市盈率与可转换债券市场价格间应存在一定关系。但根据对上海证券交易所转债的实证分析得到:目前我国转债的市场价格与其基准股票市盈率间的关系并不显著,因而市盈率指标不能作为判断转债投资价值的有效依据。     

A note on the projection properties of Hadamard matrices obtained by the first Payley construction

We show that the projections on four factors of an arbitrary orthogonal array of strength 2 allow the estimation of main effects and two-factor interactions when all other effects are assumed to be zero, if those projections satisfy the bounds given by Weils theorem. The only exceptions are the Hadamard matrices of orders 16 and 24. A consequence is again the estimability of main effects and two-factor interactions for the projections on four factors of the first Payley construction for arbitrary run size.     

基于复杂供应链库存管理策略的系统动力学研究

在分析了具有不同提前期和加工时间的复杂供应链特点基础上，研究了混合CONWIP／Kanban库存管理思想与同步CONWIP库存管理思想在复杂供应链上的应用。同时借助Vensim建模平台。针对这两种管理思想建立了基于复杂供应链系统的动态仿真模型，并对模拟结果进行了分析。     

供应链管理环境下我国中小型第三方物流企业运营解决方案

通过对目前我国中小型第三方物流企业市场现状的分析，从供应链一体化的角度，阐明了提高企业营运竞争力的重要性，并试探性地提出了有关我国中小型第三方物流企业如何在营运层面上提高竞争力的建议与解决方案：     

On the evolutionary edge of altruism: a game-theoretic proof of Hamilton’s rule for a simple case of siblings

We offer a game-theoretic proof of Hamiltons rule for the spread of altruism. For a simple case of siblings, we show that the rule can be derived as the outcome of a one-shot prisoners dilemma game between siblings.JEL Classification: A13, C70, D64Correspondence to: Oded Stark, ZEF, University of Bonn, Walter-Flex-Strasse 3, 53113 Bonn, GermanyWe are indebted to an anonymous referee and to Uwe Cantner for helpful comments and suggestions. Partial financial support from the National Institute on Aging (grant RO1-AG13037) and from the Humboldt Foundation is gratefully acknowledged.     

Voting in assemblies of shareholders and incomplete markets

Summary. An economy with two dates is considered, one state at the first date and a finite number of states at the last date. Shareholders determine production plans by voting - one share, one vote - and at -majority stable stock market equilibria, alternative production plans are supported by at most percent of the shareholders. It is shown that a -majority stable stock market equilibrium exists if where S is the number of states at the last date and J is the number of firms. Moreover, an example shows that -majority stable stock market equilibria need not exist for smaller s.Received: 23 December 2002, Revised: 14 June 2004, JEL Classification Numbers: D21, D52, D71, G39. Correspondence to: Hervé CrésThe authors are grateful to an anonymous referee for helpful comments and suggestions. Financial support from the Danish Research Councils and hospitality of HEC is gratefully acknowledged by Mich Tvede and support from Fondation HEC is gratefully acknowledged by Hervé Crés.     

影响盈余信息含量的因素——来自A股的实证结果

研究中习惯用回报／盈余关系来表示会计盈余的信息含量。通过A股的实证结果发现，当时间窗口为公告日前后60关时，回报／盈余关系较显著；盈余的持续性越高，回报／盈余关系越显著；非线性的模型比线性模型的解释能力更强。但是模型总体的R2水平都较低，这可能是由于研究方法的缺陷、市场的非理性、盈余本身信息含量低等原因造成的。     

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.