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.     

Bayesian prediction of waiting times in stochastic models

The authors show how saddlepoint techniques lead to highly accurate approximations for Bayesian predictive densities and cumulative distribution functions in stochastic model settings where the prior is tractable, but not necessarily the likelihood or the predictand distribution. They consider more specifically models involving predictions associated with waiting times for semi‐Markov processes whose distributions are indexed by an unknown parameter θ. Bayesian prediction for such processes when they are not stationary is also addressed and the inverse‐Gaussian based saddlepoint approximation of Wood, Booth & Butler (1993) is shown to accurately deal with the nonstationarity whereas the normal‐based Lugannani & Rice (1980) approximation cannot, Their methods are illustrated by predicting various waiting times associated with M/M/q and M/G/1 queues. They also discuss modifications to the matrix renewal theory needed for computing the moment generating functions that are used in the saddlepoint methods.     

应运而生的思想家——兼评《〈韩非子〉的成书与文学研究》

韩非是法家集大成的人物。其思想,是为建立统一、强大的封建帝国提供理论根据与思想方法;其著作,是顺应时代发展的产物。韩非论著中关于文学的论说都是针对当时具体社会环境与他所要完成的历史使命而言的,我们必须从他的文章所体现的与文学有关的方方面面,去了解其对文学的真正看法。所以,我们应该注意两点:第一,韩非著作中说的"文学",乃是指学术文化,主要指儒家学说。第二,韩非当时面对的是学术上的各家各派竞驰其说。其著作中的文学理论是一种特殊时期的文艺理论,并不能反映他的整个文艺观。由此出发,才有可能对韩非的文学思想有一个比较全面、正确的认识。     

休闲文学及其评价

“休闲文学”是指给读者娱乐、消遣的文学 ,它是 90年代以来文学发展的一种趋向。现当代对休闲文学审美主义和意识形态的批评 ,实际上是高等文化人对市民意识、市民情趣的文化歧视。针对当前日益勃兴的休闲文学 ,批评家应调整视角 ,公正地加以剖析     

《列王纪》英雄形象在维吾尔文学中的流传

《列王纪》中一些英雄形象活跃于维吾尔古代民间文学之中.这可能与波斯袄教的传入同时,并与伊斯兰教传入前就已根深蒂固的尚勇精神有直接的关系.     

西夏文《经史杂抄》考源

西夏文《经史杂抄》一书出土已近百年,因首尾皆佚,内容芜杂,此前一直未获全文解读,出处亦不明。本文指出此书主要依据敦煌汉文文献《新集文词九经抄》编译而来,是目前所知西夏人编译的唯一一本通篇征引汉文俗文学的作品。对它的解读可以解决夏译汉籍悬而未决的最后一个谜团,从而为研究西夏教育和文化交流提供一份宝贵的材料。     

西方文艺人才思想的发展

文章站在现代文艺学的角度,对西方文艺人才思想进行梳理,力图理清脉络,进而发现其基本特征.     

论中国精神文明与少数民族文学之关系

中国的精神文明是由汉民族和各个少数民族共同“联姻”缔造的。文学是最能体现少数民族素质的重要标志，少数民族文学对中华民族精神文明作出了巨大贡献。     

民族出身与民族文学——兼及民族文学的范畴与界定

关于少数民族文学界定的标准有题材论 ,作家论 ,作家、作品民族特点统一论 ,作家、民族文字统一论等几种有代表性的观点。这些观点大多涉及作者的民族出身问题。而由于现当代少数民族作者民族出身的复杂性 ,造成了对少数民族文学范畴和界定的混乱及不确定性。少数民族文学应是少数民族作者创作的 ,体现本民族独特审美意识和审美情趣的文学作品。