A variable-neighbourhood search algorithm for finding optimal run orders in the presence of serial correlation

The responses obtained from response surface designs that are run sequentially often exhibit serial correlation or time trends. The order in which the runs of the design are performed then has an impact on the precision of the parameter estimators. This article proposes the use of a variable-neighbourhood search algorithm to compute run orders that guarantee a precise estimation of the effects of the experimental factors. The importance of using good run orders is demonstrated by seeking D-optimal run orders for a central composite design in the presence of an AR(1) autocorrelation pattern.     

Unifying CRM and EWOC designs for phase I cancer clinical trials

The main goal of phase I cancer clinical trials is to determine the highest dose of a new therapy associated with an acceptable level of toxicity for the use in a subsequent phase II trial. The continual reassessment method (CRM) [O’Quigley, J., Pepe, M., Fisher, L., 1990. Continual reassessment method: a practical design for phase I clinical trials in cancer. Biometrics 46, 33–48] and escalation with overdose control (EWOC) [Babb, J., Rogatko, A., Zacks, S., 1998. Cancer phase I clinical trials: efficient dose escalation with overdose control. Statist. Med. 17 (10), 1103–1120] are two model-based designs used for phase I cancer clinical trials. A few modifications of the (original) CRM and EWOC have been made by many authors. In this paper, we show how CRM and EWOC can be unified and present a hybrid design. We study the characteristics of the approach of the hybrid design. The comparisons of the three designs (CRM, EWOC, and the hybrid design) are presented by convergence rates and overdose proportions. The simulation results show that the hybrid design generally has faster convergence rates than EWOC and smaller overdose proportions than CRM, especially when the true maximum tolerated dose (MTD) is above the mid-level of the dose range considered. The performance of these three designs is also evaluated in terms of sensitivity to outliers.     

Confidence interval estimation of the difference between paired AUCs based on combined biomarkers

In many diagnostic studies, multiple diagnostic tests are performed on each subject or multiple disease markers are available. Commonly, the information should be combined to improve the diagnostic accuracy. We consider the problem of comparing the discriminatory abilities between two groups of biomarkers. Specifically, this article focuses on confidence interval estimation of the difference between paired AUCs based on optimally combined markers under the assumption of multivariate normality. Simulation studies demonstrate that the proposed generalized variable approach provides confidence intervals with satisfying coverage probabilities at finite sample sizes. The proposed method can also easily provide P-values for hypothesis testing. Application to analysis of a subset of data from a study on coronary heart disease illustrates the utility of the method in practice.     

大学英语教学导入中国文化的构想

在今天,英语作为世界通用语言,其霸主地位已是不争的事实.与此同时,"汉语热"现象在国外悄然兴起.而目前中国大学生的汉语水平与对中国传统文化的了解程度是令人堪忧的.在这样的国际环境下,在大学英语教学中导入中国文化不仅是必要的,而且是急需的.具体的导入方式包括教学大纲的改革、测试内容的完善、英语教材的重新编写,中西文化对比教学等方面.     

“立人”首在“立言”——论“五四”白话文运动的语言生存观

“五四”白话文运动不是单纯的文学工具和形式的变革。文学革命者认识到文言是权力建制的工具,国人具有文字崇拜的心理,白话文运动具有推动全方位的生命解放的意义。     

美国次贷危机对我国经济的影响和启示

发生在美国次级房贷危机给全球的金融市场带来了剧烈的震荡,目前还难以预测其对世界经济的危害程度。本文深入分析了次贷危机的成因及其对我国宏观经济的影响,并总结从中获得的启示。     

新闻标题的象似性分析

象似性理论的主要原则（映像象似、拟象象似和隐喻象似等）在新闻标题的句子结构、修辞、字体、排版等方面都有体现。运用象似性理论分析新闻标题,有助于帮助读者理解新闻标题的语言特点,挖掘更多新闻背后隐含的意义。     

先锋小说中的词语超常搭配现象探微

先锋小说是20世纪80年代的一个重要的文学现象。以先锋小说中的词语超常搭配现象为研究对象,初步分析了先锋小说中的词语超常搭配在主谓结构、偏正结构、动宾结构、并列结构这四种句法结构中的体现,从而从一个侧面展现出先锋小说语言实验的特点。     

语言模糊性产生的根源探究

文章从人类的认知心理、客观事物或现象的类属划分、语言及交际活动四个方面说明了语言模糊性产生的原因。认为人类的认知能力具有不确定性和有限性,这种不确定性和有限性导致了客观事物或现象类属划分的模糊性,指称这些模糊范畴的语言也就不可避免地存在模糊性;语言和客观事物或现象是通过认知活动产生联系的,当人们对客观事物或现象产生模糊反应时,其对应的语言符号必然具有模糊性;由于其独特的语用功能,语言的模糊性成为交际的需要。     

纽马克的交际翻译理论视角下的公示语研究

公示语是一张城市名片,它不仅代表一个城市的形象,体现其文明程度,而且还直接影响到外商的投资决心。本文以纽马克的交际翻译理论为指导,通过对南宁市公示语翻译现状进行考察,探讨公示语翻译的策略。