Block empirical likelihood for longitudinal partially linear regression models

The authors propose a block empirical likelihood procedure to accommodate the within‐group correlation in longitudinal partially linear regression models. This leads them to prove a nonparametric version of the Wilks theorem. In comparison with normal approximations, their method does not require a consistent estimator for the asymptotic covariance matrix, which makes it easier to conduct inference on the parametric component of the model. An application to a longitudinal study on fluctuations of progesterone level in a menstrual cycle is used to illustrate the procedure developed here.     

Goodness-of-fit Procedures for Copula Models Based on the Probability Integral Transformation

Abstract.  Wang & Wells [ J. Amer. Statist. Assoc. 95 (2000) 62] describe a non-parametric approach for checking whether the dependence structure of a random sample of censored bivariate data is appropriately modelled by a given family of Archimedean copulas. Their procedure is based on a truncated version of the Kendall process introduced by Genest & Rivest [ J. Amer. Statist. Assoc. 88 (1993) 1034] and later studied by Barbe et al . [ J. Multivariate Anal. 58 (1996) 197]. Although Wang & Wells (2000) determine the asymptotic behaviour of their truncated process, their model selection method is based exclusively on the observed value of its L ²-norm. This paper shows how to compute asymptotic p -values for various goodness-of-fit test statistics based on a non-truncated version of Kendall's process. Conditions for weak convergence are met in the most common copula models, whether Archimedean or not. The empirical behaviour of the proposed goodness-of-fit tests is studied by simulation, and power comparisons are made with a test proposed by Shih [ Biometrika 85 (1998) 189] for the gamma frailty family.     

Empirical likelihood tests for two‐sample problems via nonparametric density estimation

The authors study the problem of testing whether two populations have the same law by comparing kernel estimators of the two density functions. The proposed test statistic is based on a local empirical likelihood approach. They obtain the asymptotic distribution of the test statistic and propose a bootstrap approximation to calibrate the test. A simulation study is carried out in which the proposed method is compared with two competitors, and a procedure to select the bandwidth parameter is studied. The proposed test can be extended to more than two samples and to multivariate distributions.     

群组AHP排序的最小最大几何距离方法

对群组判断矩阵提出一种新的最小最大几何距离排序方法(MGDM)。鉴于不同专家所给判断矩阵质量上的差异,MGDM对群组判断矩阵进行不同程度的加权处理,并进行群组一致性检验。     

足球运动员耐力素质及训练方法分析

足球运动员的耐力素质是技战术的保证。本文对足球运动员的耐力素质的情况,特点和影响耐力素质的主要因素进行了分析,总结了提高耐力素质的具体训练方法和手段。     

对股权分置改革对价问题的市场分析——通过股权分置改革试点阶段G股的市场表现认识对价的特征

股权分置改革作为一场促进我国资本市场健康发展的制度性变革,给股市带来了生机,G股的活跃表现为投资者创造了更多的投资机会。在股权分置改革试点阶段,试点企业推出的对价方案呈现出对价方式的多样性、对价水平的差异性、对价依据的非统一性和调整对价的随意性等多种市场特征。对价方式的多样性为投资者提供了更多的市场机会,对价水平的高低差异反映了不同的对价成本,对价依据的差异性是导致不同对价水平的主要原因,上市公司频繁调整对价方案缘于非流通股股东与流通股股东的沟通和交流。     

利用现代教育技术促进学习方式变革

随着信息时代的到来以及网络技术的迅猛发展,人们的学习方式发生了深刻的变革。现代教育技术的逐步普及与发展,为学习方式开拓了广阔的天地。当前教育改革的一项具体目标就是要改善学习者的学习方式,而以信息技术为基础的现代教育技术在转变学习者的学习方式过程中具有独特的优势,这种优势决定了它在教育改革中扮演着重要的角色。     

我国外语实证研究工具层面问题分析

我国现阶段外语实证研究存在两大工具层面的问题:(1)虚构统计量与误用统计方法或统计量;(2)论证违反逻辑规则。这些问题的表现形式多种多样,即使在外语类核心学术期刊登载的研究报告中也不鲜见。虽然主要原因是我国外语教育研究者对实证研究所需要的统计学与逻辑学学科体系了解不足,但有的高层次研究者在虚构时所表现的胆大妄为与无所顾忌,也实在令人诧异。     

欧美当代技术哲学的“经验转向”：内涵、依据和存在的问题

指出欧美当代技术哲学研究中的"经验转向"不是把这一哲学的分支学科转变为经验科学,也不是使它远离规范性内容,而是要求把关于技术及其效果的哲学分析建立在对技术的充分的经验描述之上.阐释了这一转向的存在根据即技术人造物具有的二元特性,即结构特性和功能特性,论述了这一转向在技术哲学的本体论、认识论、伦理学和社会政治理论等各领域中的表现,分析了不同学者对这个问题的不同观点,并就"经验转向"相关的某些问题作了进一步思考,提出了建设性的建议.     

有关股评价值的实证研究

以2000年股评家推荐的2052只股票作为样本,并根据推荐的持有策略将其分成短线和中线两组来分析股评的投资价值.研究结果对我国股评家属于信息驱动型提出了质疑,并指出,即使考虑交易费用,被推荐的短、中线个股(组合)仍然具有一定的投资价值.从长期来看,个股(组合)可以显著获得超常收益或赢利;与中线相比,短线个股(组合)的期望收益较高、风险较小.