Extension of two-sided test to multiple treatment trials

In a two-treatment trial, a two-sided test is often used to reach a conclusion, Usually we are interested in doing a two-sided test because of no prior preference between the two treatments and we want a three-decision framework. When a standard control is just as good as the new experimental treatment (which has the same toxicity and cost), then we will accept both treatments. Only when the standard control is clearly worse or better than the new experimental treatment, then we choose only one treatment. In this paper, we extend the concept of a two-sided test to the multiple treatment trial where three or more treatments are involved. The procedure turns out to be a subset selection procedure; however, the theoretical framework and performance requirement are different from the existing subset selection procedures. Two procedures (exclusion or inclusion) are developed here for the case of normal data with equal known variance. If the sample size is large, they can be applied with unknown variance and with the binomial data or survival data with random censoring.     

Local Power Analyses of Goodness-of-fit Tests for Copulas

Abstract.  The asymptotic behaviour of several goodness-of-fit statistics for copula families is obtained under contiguous alternatives. Many comparisons between a Cramér–von Mises functional of the empirical copula process and new moment-based goodness-of-fit statistics are made by considering their associated asymptotic local power curves. It is shown that the choice of the estimator for the unknown parameter can have a significant influence on the power of the Cramér–von Mises test and that some of the moment-based statistics can provide simple and efficient goodness-of-fit methods.     

论篇章性的构成标准

篇章性(textuality)是篇章语言学的核心.在过去几十年中,语言学界提出了篇章性的一些构成要素,其中Beaugrande和Dressler详细论述了篇章性的七个构成标准.本文首先简述篇章性、篇章性的标准,最后提出笔者对于七个标准相互间关系的看法.     

实时CORBA rtORB的性能评估

介绍了一个实时CORBA的原型rtORB,给出了一个对其进行实时性能测试的平台。以延迟和延迟抖动为指标,通过与其他实时CORBA的性能比较,表明rtORB可以支持实时应用。为评估操作系统和通信对实时CORBA的影响,在不同操作系统上进行了测试。针对rtORB在不同操作系统上的测试结果,讨论了操作系统和通信对基于实时CORBA实时应用的影响。     

大学英语四六级考试改革的政策研究

大学英语四六级考试改革需要正确的政策引导。为了推进大学英语四六级考试的协调、稳步发展,应树立全面的英语考试评价观,理顺大学英语四六级考试与英语教学的关系,借鉴国外先进的考试技术与管理经验,加强大学英语四六级考试的安全管理。     

B/S模式的PSC现代化管理系统的构建

探索网络环境下的普通话测试与管理,已经成为一个很重要的课题。本文主要研究B/S模式下的PSC现代化管理系统构建,从硬件、软件、网络服务各方面提出设计理念。     

试论法学专业考试制度的改革与创新

现行法科考试制度使大学法学教育沦落为应试教育,既丧失了法学教育的独立性,也造成了法学教育与司法实务、社会适用的严重脱节.本文通过对现行法科考试制度和法学专业考试所特有的弊端分析,提出了对教师加强教育、教学基础理论的学习,提高教师命题的技能;建立健全相关考试制度;更新法学专业教育理念、准确定位教学目标等改革建议.     

中国农业信贷与农业GDP（1978～2001）——一个Granger因果关系检验

信贷资金一直是中国农业资金最重要的来源之一 ,误差修正模型对 1978～ 2 0 0 1年间中国农业GDP与农业信贷作出了Granger因果关系检验。结果表明 ,中国农业GDP与农业信贷存在显著的协整关系 ,并且无论是长期还是短期 ,农业信贷都是农业GDP的Granger原因 ,这表明农业信贷投入对中国农业增长存在着重要的影响     

Multivariate Life Testing in Variably Scaled Environments

This paper examines modeling and inference questions for experiments in which different subsets of a set of k possibly dependent components are tested in r different environments. In each environment, the failure times of the set of components on test is assumed to be governed by a particular type of multivariate exponential (MVE) distribution. For any given component tested in several environments, it is assumed that its marginal failure rate varies from one environment to another via a change of scale between the environments, resulting in a joint MVE model which links in a natural way the applicable MVE distributions describing component behavior in each fixed environment. This study thus extends the work of Proschan and Sullo (1976) to multiple environments and the work of Kvam and Samaniego (1993) to dependent data. The problem of estimating model parameters via the method of maximum likelihood is examined in detail. First, necessary and sufficient conditions for the identifiability of model parameters are established. We then treat the derivation of the MLE via a numerically-augmented application of the EM algorithm. The feasibility of the estimation method is demonstrated in an example in which the likelihood ratio test of the hypothesis of equal component failure rates within any given environment is carried out.     

低渗气藏多次应力敏感测试及应用

低渗透气田在我国已开发气藏中占有相当大比例，应力敏感性对气田开发的影响已逐渐引起人们重视。针对目前大多数低渗透气田应力敏感测试仍然采用定内压变围压测试方式所存在的与实际气田开发过程中内压变化上覆压力恒定的变化规律不一致的问题，研究提出了变内压定围压测试方法，采用该方式测试低渗透岩芯在净上覆压力六升六降过程中应力敏感性,并应用测试的应力敏感曲线对低渗透气井试井特征及单井生产动态进行研究。结果表明：变内压定围压测试方法更接近于气田实际压力变化过程；（不）考虑应力敏感试井分析两者在试井特征曲线第II阶段相差较大，五开五关试井分析表明渗透率应力敏感效应的存在对气藏的开发是不利的；应力敏感对单井模拟井底流压影响很大，考虑应力敏感时，气井生产压差明显增大。因此，在低渗透气田开发过程中，必须注意应力敏感对气田开发的影响。