Comparing Pearson Correlations: Dealing with Heteroscedasticity and Nonnormality

Methods for computing a confidence interval for the difference between two Pearson correlations are compared when dealing with nonnormality and heteroscedasticity. Variations of a method derived by Zou performed relatively well in simulations for the dependent case. For the independent case, the Wilcox–Muska method performed best.     

A Comparison of Estimation Methods on the Coverage Probability of Satterthwaite Confidence Intervals for Assay Precision with Unbalanced Data

Construction of closed-form confidence intervals on linear combinations of variance components were developed generically for balanced data and studied mainly for one-way and two-way random effects analysis of variance models. The Satterthwaite approach is easily generalized to unbalanced data and modified to increase its coverage probability. They are applied on measures of assay precision in combination with (restricted) maximum likelihood and Henderson III Type 1 and 3 estimation. Simulations of interlaboratory studies with unbalanced data and with small sample sizes do not show superiority of any of the possible combinations of estimation methods and Satterthwaite approaches on three measures of assay precision. However, the modified Satterthwaite approach with Henderson III Type 3 estimation is often preferred above the other combinations.     

VARIABLE SELECTION AND INTERPRETATION OF COVARIANCE PRINCIPAL COMPONENTS

In practice, when a principal component analysis is applied on a large number of variables the resultant principal components may not be easy to interpret, as each principal component is a linear combination of all the original variables. Selection of a subset of variables that contains, in some sense, as much information as possible and enhances the interpretations of the first few covariance principal components is one possible approach to tackle this problem. This paper describes several variable selection criteria and investigates which criteria are best for this purpose. Although some criteria are shown to be better than others, the main message of this study is that it is unwise to rely on only one or two criteria. It is also clear that the interdependence between variables and the choice of how to measure closeness between the original components and those using subsets of variables are both important in determining the best criteria to use.     

Coherent Hypothesis Testing

Multiple hypothesis testing, an important quantitative tool to report the results of scientific inquiries, frequently leads to contradictory conclusions. For instance, in an analysis of variance (ANOVA) setting, the same dataset can lead one to reject the equality of two means, say μ₁ = μ₂, but at the same time to not reject the hypothesis that μ₁ = μ₂ = 0. These two conclusions violate the coherence principle introduced by Gabriel in 1969 Gabriel, K. R. (1969), “Simultaneous Test Procedures - Some Theory of Multiple Comparisons,” The Annals of Mathematical Statistics, 40, 224–250. Available at http://www.jstor.org/stable/2239213[Crossref] , [Google Scholar], and lead to results that are difficult to communicate, and, many times, embarrassing for practitioners of statistical methods. Although this situation is common in the daily life of statisticians, it is usually not discussed in courses of statistics. In this work, we enrich the teaching and discussion of this important topic by investigating through a few examples whether several standard test procedures are coherent or not. We also discuss the relationship between coherent tests and measures of support. Finally, we show how a Bayesian decision-theoretical framework can be used to build coherent tests. These approaches to coherence enlighten when such property is appealing in multiple testing and provide means of obtaining it.     

气候变化对自然保护区的影响及法律对策研究

随着气候变化问题的加剧,自然保护区缺乏应对气候变化的相应措施,造成其保护珍稀资源的功能受到了限制。为了解决这一问题,有必要分析研究气候变化对自然保护区的影响,提出相应的法律对策,以期使自然保护区保护珍稀资源的功能得到最大的发挥。     

新疆城市民族工作的新问题及对策研究

城市化进程中,各种关系错综复杂,做好城市民族工作应注意不同民族间的利益,新疆城市民族工作由于宗教信仰、风俗习惯不同、传统文化的差异性、生活方式和价值取向多样化,使得民族工作出现了新问题,经过调查和研究,提出了以下对策：大力宣传党的民族宗教政策,不断强化公民教育;加强城市社区管理,塑造城市少数民族的居住格局;加强城市流动人口管理;恐怖暴力事件影响大,打击恐怖实刻不容缓;坚决维护边疆地区稳定,保持地区安定团结局面;积极推进新疆城市民族工作的法制建设。     

高校领导干部必须高度重视讲政治

讲政治是新形势下党中央对高校领导干部提出的新的更高的要求，是端正办学方向的重要前提，是培养合格人才的思想基础，是成为社会主义政治家、教育家的先决条件。当前，高校领导干部在讲政治方面还存在着理想信念不是很坚定、贯彻党的基本路线不够自觉、办学方向时有摇摆、不能很好处理“政治”与“业务”的关系等问题，因此，必须加强理论学习，深入贯彻党的教育方针，深化教育改革，加强思想政治工作，维护安定团结的大好形势，不断加强班子自身建设。     

桂平文化旅游开发研究

桂平文化类型多样,比较有特点的是区域内的民俗文化、宗教文化和历史文化,这些文化资源以其独特的风格成为地区垄断性的旅游产品。针对桂平文化旅游开发中的现状问题,从品牌建设,宣传手段,人才培养,可持续发展等方面提出发展对策。     

广西非物质文化遗产保护问题与对策

广西有12个世居民族,各民族在长期的历史发展进程中,不仅创造了大量有形的物质文化遗产,而且创造了丰富的非物质文化遗产,这些遗产承载着民族精神和情感,维系着国家统一和民族团结,联系着世界的人类智慧,是广西各民族千百年来创造的智慧结晶,是传承各民族文化根脉的宝贵资源财富。广西非物质文化遗产保护工作近年取得了一定的成绩,但也面临不少问题需要解决。     

试论明代中国应对西欧殖民者的得与失

15世纪至16世纪之交地理大发现后,西欧殖民者先后来到世界东方,各地区间封闭状态被打破,明朝遇到了如何应对即将急剧强大起来的西欧殖民者的问题。明朝应采取的正确应对措施,主要者应包括四项:迅速调查西欧殖民者的情况、努力发展本国的对外贸易、积极学习欧洲先进的科技知识、大力发展能与西欧殖民者相抗衡的国防力量。而明朝在这几方面做得有正有误,消极和积极的两种表现大体平衡。这使其时中国的发展速度低于西欧殖民者,国力对比朝着有利于后者的方向演变。只是由于明朝土广民众、原有国力相当强大,其综合国力直至该朝灭亡也没达到小于西欧殖民者的地步。后来清朝发展了明朝以上四个措施的消极面,加速了中国的衰弱。明朝的经验和教训说明,地理大发现后,各国必须在全球性的国际交往中应对得法,才能使之避免被动,保持富强;而时刻注意即将发生深刻影响的新动向,才能保证应对得法。