A BETA-OPTIMAL TEST OF THE EQUICORRELATION COEFFICIENT

This paper considers the problem of testing for nonzero values of the equicorrelation coefficient of a standard symmetric multivariate normal distribution. Recently, SenGupta (1987) proposed a locally best test. We construct a beta-optimal test and present selected one and five percent critical values. An empirical power comparison of SenGupta's test with two versions of the beta-optimal test and the power envelope shows the relative strengths of the three tests. It also allows us to assess and confirm Efron's (1975) rule of when to question the use of a locally best test, at least for this testing problem. On the basis of these results, we argue that the two beta-optimal tests can be considered as approximately uniformly most powerful tests, at least at the five percent significance level.     

基于分形理论的时尚商品价格预测问题研究

在研究时尚商品价格规律及影响因素的复杂性、不确定性的基础之上，提出了基于分形理论的时尚商品价格预测新方法。该方法首先运用重标极差法分析了时尚商品价格时间序列预测的可行性，然后根据分形统计模型，得到时尚商品历史价格时间序列的分形维数，通过不断增加新销售或预测得到新的记录方法，求得增加新记录后的新分形维数，由此可以预测出下一时间单位的商品销售价格。通过实例进行了方法检验和结果比较，取得了较为理想的预测结果，证明了该方法的可行性和有效性。     

Statistical mechanical analysis of the dynamics of learning in perceptrons

We describe the application of tools from statistical mechanics to analyse the dynamics of various classes of supervised learning rules in perceptrons. The character of this paper is mostly that of a cross between a biased non-encyclopaedic review and lecture notes: we try to present a coherent and self-contained picture of the basics of this field, to explain the ideas and tricks, to show how the predictions of the theory compare with (simulation) experiments, and to bring together scattered results. Technical details are given explicitly in an appendix. In order to avoid distraction we concentrate the references in a final section. In addition this paper contains some new results: (i) explicit solutions of the macroscopic equations that describe the error evolution for on-line and batch learning rules; (ii) an analysis of the dynamics of arbitrary macroscopic observables (for complete and incomplete training sets), leading to a general Fokker–Planck equation; and (iii) the macroscopic laws describing batch learning with complete training sets. We close the paper with a preliminary expose´ of ongoing research on the dynamics of learning for the case where the training set is incomplete (i.e. where the number of examples scales linearly with the network size).     

《商洛学院学报》2000～2005年作者信息统计分析

利用文献计量学方法,以《商洛学院学报》2000~2005年发表的844篇论文为统计样本,对载文的作者信息进行统计分析和研究。结果显示,高校教师是学报的主要作者群;正高级职称作者发文占6.99%,副高级职称作者发文占23.50%,中级职称作者发文占54.11%,初级职称及无职称作者发文占15.40%;独著占82.71%,二人合著占15.37%,三人以上合著占1.92%;本校作者发文占65.29%,本省作者发文占27.13%,外省作者发文占7.58%;6年间共产生核心作者90人,其中杰出作者4人。     

高校毕业生就业率统计方法探析

随着我国由计划经济体制向市场经济体制转变，大学生就业也由统包统配向自主择业转变，高校就业率统计工作如何适应形势的发展，从而能够科学、准确地反映出高校实际的就业状况和办学水平，使之能够促进高校教育健康发展是一个值得研究的课题，本文主要总结了我国近年来就业率统计方式的形成、演变过程及现行就业率统计中存在的问题，为就业率统计方法的改革研究奠定基础。     

论科学与工程的结构性差异

工程最初被理解为自然科学的应用,然而科学与工程之间的区别是需要进一步澄清的。二者间最简单的区别表现在自然物的科学同人造物的科学之间的区别,而创造性并不能作为科学同工程之间的根本区别。工程师寻找实现目标的手段,手段则是由规则给出的,而且是在技术可能性上有效的。为了更好地理解工程,需要引入技术解释学,并且把工程科学的哲学溶入技术的形而上学之中。     

江西流动人口规模的统计预测与分析

据有关数据显示,江西省目前有300多万的流动人口规模,随着经济的发展,江西省的流动人口将趋于增长。文章利用统计预测方法,从三种不同的角度预测了江西省从2005~2050年的流动人口规模,并对如何加强其管理进行了探讨。     

技术哲学研究中的二元化问题探析

技术人工物的两重性问题、技术伦理的二元划分和技术-社会研究模式确立等二元化问题已然成为时下技术哲学研究的重要视点。结构-功能、结构-意向性的“二元组成”是从技术设计的视角来打开技术黑箱的必由之路;设计伦理和使用伦理的“二元分割”,使得技术伦理研究包括动态嵌入和事后规范两个向度;技术-社会“二元依存”模型的建构,使得技术研究从脱域回归至返域的境遇中来。     

A survey on multivariate chi-square distributions and their applications in testing multiple hypotheses

We are concerned with three different types of multivariate chi-square distributions. Their members play important roles as limiting distributions of vectors of test statistics in several applications of multiple hypotheses testing. We explain these applications and consider the computation of multiplicity-adjusted p-values under the respective global hypothesis. By means of numerical examples, we demonstrate how much gain in level exhaustion or, equivalently, power can be achieved with corresponding multivariate multiple tests compared with approaches which are only based on univariate marginal distributions and do not take the dependence structure among the test statistics into account. As a further contribution of independent value, we provide an overview of essentially all analytic formulas for computing multivariate chi-square probabilities of the considered types which are available up to present. These formulas were scattered in the previous literature and are presented here in a unified manner.     

Using repeated-prevalence data in multi-state modeling of renal replacement therapy

Multi-state models help predict future numbers of patients requiring specific treatments but these models require exhaustive incidence data. Deriving reliable predictions from repeated-prevalence data would be helpful. A new method to model the number of patients that switch between therapeutic modalities using repeated-prevalence data is presented and illustrated. The parameters and goodness of fit obtained with the new method and repeated-prevalence data were compared to those obtained with the classical method and incidence data. The multi-state model parameters’ confidence intervals obtained with annually collected repeated-prevalence data were wider than those obtained with incidence data and six out of nine pairs of confidence intervals did not overlap. However, most parameters were of the same order of magnitude and the predicted patient distributions among various renal replacement therapies were similar regardless of the type of data used. In the absence of incidence data, a multi-state model can still be successfully built with annually collected repeated-prevalence data to predict the numbers of patients requiring specific treatments. This modeling technique can be extended to other chronic diseases.