Comparison of estimators of the location parameter using pitman's closeness criterion

Necessary and sufficient conditions for a linear estimator to dominate another linear estimator of a location parameter under the Pitman's criterion of comparison are discussed. Consequently it is demonstrated that a linear biased estimator can not dominate a linear unbiased estimator under Pitman's criterion and that the sample mean is the Closest Linear Unbiased Estimator (CLUE). It is also shown that the ridge regression estimator with a known biasing constant can not dominate the ordinary least squares estimator. If an estimator δdominates an estimator δin the average loss sense then sufficient conditions are obtained under which δis also preferred over δunder Pitman's criterion. Further we obtain sufficient conditions under which preference under the Pitman's criterion will lead to preference under the mean squared error sense.     

On estimating the dimensionality in discriminant analysis

In discriminant analysis, the dimension of the hyperplane which population mean vectors span is called the dimensionality. The procedures commonly used to estimate this dimension involve testing a sequence of dimensionality hypotheses as well as model fitting approaches based on (consistent) Akaike's method, (modified) Mallows' method and Schwarz's method. The marginal log-likelihood (MLL) method is developed and the asymptotic distribution of the dimensionality estimated by this method for normal populations is derived. Furthermore a modified marginal log-likelihood (MMLL) method is also considered. The MLL method is not consistent for large samples and two modified criteria are proposed which attain asymptotic consistency. Some comments are made with regard to the robustness of this method to departures from normality. The operating characteristics of the various methods proposed are examined and compared.     

金融危机对劳动者权益的影响及保护对策

世界性金融危机对我国经济产生了巨大冲击，经济下滑，企业倒闭、裁员、欠薪、断保甚至雇主欠薪逃匿等问题不断发生。在我国社会保障体制尚不完善的情况下，金融危机对劳动者权益的影响远胜于对企业的影响。在危机应对中，保护劳动者合法权益，关系到我国劳动关系能否和谐稳定的终极目标的实现。一方面要依据国家统一立法，贯彻劳动法倾斜保护的基本原则；另一方面，应当积极推进劳资协商对话机制，使之成为我国劳动者权益保护的主流模式。     

《唐诗选》及其关系书研究述评

明代旧题李攀龙《唐诗选》及相关书在中国和日本都有广泛的传播，版本众多，中日学者围绕《唐诗选》所展开的研究也取得了很多成果，涉及到版本辨伪，重版类版．影响研究等多个方面。研究向前推进的同时也看到无论是文献的收集整理还是在此基础上的文学思想研究．都还有很大的研究空间。     

顾客满意之谜

顾客满意是现代市场营销以及其他管理学科的核心概念。但是迄今为止,国内外学者还没有就顾客满意的定义等达成共识。本文在对顾客满意的定义、形成原因进行理论研究的基础上,分析了顾客满意对企业绩效的作用,最后探讨了顾客满意理论未来的研究方向。     

当代文学史的结构问题

在文学史的体例布局上,各种古代或现代文学史通常以代表作家和经典作品为结构主线,但近二十年的七十多种中国当代文学史在重读历史语境时,却主要突出题材、思潮、论争和现象,而不是以作家、作品为章节题目。这或者是因为价值观念系统混乱和文学史书写距离太近导致当代文学正典化的困难,又或者是由于中国当代文学特殊生产环境的主要创造物,首先是现象思潮而非作家作品。本文试图从20世纪50年代以来的文学体制、80年代知识分子与主流意识形态的合作与冲突之互动关系,以及近二十年来文学史写作者及当代文学评论者的学术背景变化等三个方面,来讨论当代文学史的这种重现象思潮轻作家文本的结构方式。     

简论语料库与教师角色之转变

现代电子语料库已有了近50年的发展，但语料库应用于课堂教学才刚刚起步。通过近年语料库辅助课堂教学诸多实践研究，教师们不仅可以获得教学中的例句，还可引导学生们学习更地道、更准确的表达方式。     

义和团时期的清流派

徐桐、载漪等人深受儒家经典影响,忧国忧民,廉洁奉公,堪称良吏。但是,对已经发生巨变的国际局势并不了解,认为学习外国先进技术、先进思想,就是离经叛道,将导致亡国灭种。他们的思想,落后于不断前进的时代潮流,终于被时代所淘汰。     

Reporting cumulative proportion of subjects with an adverse event based on data from multiple studies

Experience has shown us that when data are pooled from multiple studies to create an integrated summary, an analysis based on naïvely‐pooled data is vulnerable to the mischief of Simpson's Paradox. Using the proportions of patients with a target adverse event (AE) as an example, we demonstrate the Paradox's effect on both the comparison and the estimation of the proportions. While meta analytic approaches have been recommended and increasingly used for comparing safety data between treatments, reporting proportions of subjects experiencing a target AE based on data from multiple studies has received little attention. In this paper, we suggest two possible approaches to report these cumulative proportions. In addition, we urge that regulatory guidelines on reporting such proportions be established so that risks can be communicated in a scientifically defensible and balanced manner. Copyright © 2010 John Wiley & Sons, Ltd.