An approximation algorithm for the <Emphasis Type="Italic">k</Emphasis>-level capacitated facility location problem

We consider the k-level capacitated facility location problem (k-CFLP), which is a natural variant of the classical facility location problem and has applications in supply chain management. We obtain the first (combinatorial) approximation algorithm with a performance factor of \(k+2+\sqrt{k^{2}+2k+5}+\varepsilon\) (ε>0) for this problem.     

Maximizing Business Returns to Corporate Social Responsibility (CSR): The Role of CSR Communication

By engaging in corporate social responsibility (CSR) activities, companies can not only generate favorable stakeholder attitudes and better support behaviors (e.g. purchase, seeking employment, investing in the company), but also, over the long run, build corporate image, strengthen stakeholder–company relationships, and enhance stakeholders' advocacy behaviors. However, stakeholders' low awareness of and unfavorable attributions towards companies' CSR activities remain critical impediments in companies' attempts to maximize business benefits from their CSR activities, highlighting a need for companies to communicate CSR more effectively to stakeholders. In light of these challenges, a conceptual framework of CSR communication is presented and its different aspects are analyzed, from message content and communication channels to company- and stakeholder-specific factors that influence the effectiveness of CSR communication.     

中国英语学习者使用非词语化名词thing特点分析--基于语料库的调查研究

非词语化是普遍存在的语言现象,而thing是常用的非词语化词之一。基于一个中国学习者语料库和一个本族语者语料库的对比,研究了中国学习者使用thing的特点。结果表明,中国学习者倾向于过度使用该词,而且存在许多语义模糊、冗余、替代和搭配不当的用法;但随着语言水平的提高,该词的使用频率显著下降,这说明中国学习者对该词的使用符合中介语的发展规律。结合研究结果尝试分析了这些特点的成因,发现学习者的词汇能力、学习策略、语言负迁移和中介语心理认知机制等因素造成了中国学习者过度及不当使用thing的现象。     

以党的群众路线教育活动推进大学生思想政治教育工作精细化

高校群众路线教育实践活动为高校思想政治教育精细化提供了契机。面对高校在校生数量的连年增加,教育对象的差异性给思想政治教育工作提出了严峻挑战。从思想政治教育体现出的许多新特点来看,学生教育精细化管理的创新是必然趋势。要通过建立健全运行机制、建立信息管理系统,增强精细化思想政治教育的执行力,才能确保高校思想政治教育精细化工作的有效开展。     

试论高校“思想政治理论课”教师教育教学能力提升

高校＂思想政治理论课＂教学具有鲜明的时代性特征,新形势下多元化的价值取向对教师的教育教学能力提出了新要求,而当前高校＂思想政治理论课＂教师教育教学能力呈现出知识结构亟待更新、教学模式单一、忽视现代网络技术、教学效果不佳等问题。可以通过政府加大经费支持力度、高校组织教学观摩展评、教师积极参加培训和交流加强集体备课的措施,提升＂思想政治理论课＂教师教育教学能力,促进教师的身心健康及专业发展,改善教学效果。     

An Application of EM Algorithm to a Change-Point Problem

We consider the problem of change-point in a classical framework while assuming a probability distribution for the change-point. An EM algorithm is proposed to estimate the distribution of the change-point. A change-point model for multiple profiles is also proposed, and EM algorithm is presented to estimate the model. Two examples of Illinois traffic data and Dow Jones Industrial Averages are used to demonstrate the proposed methods.     

Vector random fields with compactly supported covariance matrix functions

The objective of this paper is to construct covariance matrix functions whose entries are compactly supported, and to use them as building blocks to formulate other covariance matrix functions for second-order vector stochastic processes or random fields. In terms of the scale mixture of compactly supported covariance matrix functions, we derive a class of second-order vector stochastic processes on the real line whose direct and cross covariance functions are of Pólya type. Then some second-order vector random fields in R^d${\mathbb{R}}^d$ whose direct and cross covariance functions are compactly supported are constructed by using a convolution approach and a mixture approach.     

Model averaging for M-estimation

M-estimation is a widely used technique for robust statistical inference. In this paper, we study model selection and model averaging for M-estimation to simultaneously improve the coverage probability of confidence intervals of the parameters of interest and reduce the impact of heavy-tailed errors or outliers in the response. Under general conditions, we develop robust versions of the focused information criterion and a frequentist model average estimator for M-estimation, and we examine their theoretical properties. In addition, we carry out extensive simulation studies as well as two real examples to assess the performance of our new procedure, and find that the proposed method produces satisfactory results.     

Regression analysis of case-cohort studies in the presence of dependent interval censoring

The case-cohort design is widely used as a means of reducing the cost in large cohort studies, especially when the disease rate is low and covariate measurements may be expensive, and has been discussed by many authors. In this paper, we discuss regression analysis of case-cohort studies that produce interval-censored failure time with dependent censoring, a situation for which there does not seem to exist an established approach. For inference, a sieve inverse probability weighting estimation procedure is developed with the use of Bernstein polynomials to approximate the unknown baseline cumulative hazard functions. The proposed estimators are shown to be consistent and the asymptotic normality of the resulting regression parameter estimators is established. A simulation study is conducted to assess the finite sample properties of the proposed approach and indicates that it works well in practical situations. The proposed method is applied to an HIV/AIDS case-cohort study that motivated this investigation.