金融市场风险测量方法综述

近十来年,风险测量方法在收益和风险剧烈波动的股票市场中的作用日益突出,无论是金融机构还是监管当局对金融市场风险的管理与测量也都给予了足够的重视,回顾与展望金融市场风险测量研究方法对于该方面的研究也具有一定的积极意义.     

产业集聚与两阶段区域创新绩效——基于区域技术要素强度门槛的实证研究

基于价值链视角,将区域创新活动分为知识创新阶段和成果转化阶段,使用2009-2020年我国内地30个省级面板数据,以区域技术要素强度为门槛变量,探讨产业集聚对两阶段区域创新绩效的不同影响.研究发现,产业集聚对区域创新绩效的影响在两个阶段具有显著的非线性门槛特征.在知识创新阶段,随着区域技术要素强度提高,产业集聚对区域创新绩效的促进作用呈阶段性增强;在成果转化阶段,当区域技术要素强度提高时,产业集聚对区域创新绩效的影响表现为先抑制后促进.     

影响我国电信业发展的经济因素的实证分析

本文利用1991-2002年的时间序列数据,对影响我国电信业发展环境的经济因素———经济发展水平、市场化程度、产业结构变动、储蓄存款增长、城镇化程度、固定资产投资增长额、科技化水平等因素进行实证分析,并提出建议。     

Is more IT offshoring better?: An exploratory study of western companies offshoring to South East Asia

We explore the link between a company's performance and the extent of its offshoring of IT-enabled services, focusing on large western companies. Our performance measures comprise sales, profit as percentage of sales, profit/employee and sales/employee over 1999–2004. To measure offshoring, we consider the extent to which these companies have offshored: (1) software development and other IT-related development and maintenance, (2) business processes such as payroll or claims processing, and (3) call centers. We performed cluster analysis using the three corresponding offshoring variables to obtain broad patterns of offshoring. Then we compared the average performance of the companies in different clusters using ANOVA; did a regression analysis of the performance measures against the three offshoring variables; and performed non-parametric correlations within industry sectors. None of these tests indicated any clear link between company performance and the extent of offshoring thus suggesting that further study is needed to understand when to offshore and how best to do it.     

我国现阶段贫富差距的经济学分析

改革开放以来,在经济增长的同时我国的贫富分化现象也日益严峻,体现在基尼系数的变化、城乡收入差距的扩大、行业差异、地区差距、居民家庭财产集中度等一系列领域。传统城乡二元经济结构的存在、不合理的社会保障模式、经济领域的不平等竞争是导致贫富差距扩大的主要原因。政府必须利用各种经济、法律手段调节收入分配,缔造公平的竞争环境,同时加强以社会保障为主体的制度建设。     

公共资本和私人资本的生产效率及其区域差异——基于分位数回归模型的研究

本文基于中国各省区市1994～2005年的样本数据,利用分位数回归估计了各区域和各省区市的公共资本和私人资本在各分位点的产出弹性,主要结论是:私人资本的产出弹性远远大于公共资本,私人资本的产出弹性系数均为正,且基本上显著;而对于公共资本,除少数省区市外,东中部各省区市的产出弹性系数为正,而西部省区市的弹性系数则基本上为负,且大多数并不显著。各省区市的公共资本和私人资本不仅在产出弹性大小上存在较大差异,而且在条件分布的不同分位点,其弹性的变化规律也不尽相同。     

既有结构可靠度的模糊算法

基于结构抗力和荷载效应的不确定性，提出了一种既有结构工程可靠度的模糊算法。该方法利用模糊算法可以反映客观事物因素的层次性，又便于比较和考虑各层次中诸因素作用的大小以决定可靠度。算例结果表明该方法简单实用，其模型可以很好地拟合真实的极限状态函数，是解决既有结构体系可靠度问题的有效方法。     

Stationary measures for some Markov chain models in ecology and economics

Summary. Let continuous, exists in for x in . Let be an i.i.d. sequence from F and X₀ be a nonnegative random variable independent of . Let be the Markov chain generated by the iteration of random maps by . Such Markov chains arise in population ecology and growth models in economics. This paper studies the existence of nondegenerate stationary measures for {X_n}. A set of necessary conditions and two sets of sufficient conditions are provided. There are some convergence results also. The present paper is a generalization of the work on random logistics maps by Athreya and Dai (2000).Received: 20 March 2002, Revised: 4 December 2002, JEL Classification Numbers: C22, D9.The author wishes to thank Professor Mukul Majumdar and the referees for several useful suggestions.