A robust test for autocorrelation in the presence of a structural break in variance

It has been known that when there is a break in the variance (unconditional heteroskedasticity) of the error term in linear regression models, a routine application of the Lagrange multiplier (LM) test for autocorrelation can cause potentially significant size distortions. We propose a new test for autocorrelation that is robust in the presence of a break in variance. The proposed test is a modified LM test based on a generalized least squares regression. Monte Carlo simulations show that the new test performs well in finite samples and it is especially comparable to other existing heteroskedasticity-robust tests in terms of size, and much better in terms of power.     

Computational approach test for inference about several correlation coefficients: Equality and common

In this article, we consider inference about the correlation coefficients of several bivariate normal distributions. We first propose computational approach tests for testing the equality of the correlation coefficients. In fact, these approaches are parametric bootstrap tests, and simulation studies show that they perform very satisfactory, and the actual sizes of these tests are better than other existing approaches. We also present a computational approach test and a parametric bootstrap confidence interval for inference about the parameter of common correlation coefficient. At the end, all the approaches are illustrated using two real examples.     

A comparative study of confidence intervals for negative binomial proportion

In this paper, we investigate four existing and three new confidence interval estimators for the negative binomial proportion (i.e., proportion under inverse/negative binomial sampling). An extensive and systematic comparative study among these confidence interval estimators through Monte Carlo simulations is presented. The performance of these confidence intervals are evaluated in terms of their coverage probabilities and expected interval widths. Our simulation studies suggest that the confidence interval estimator based on saddlepoint approximation is more appealing for large coverage levels (e.g., nominal level≤1% ) whereas the score confidence interval estimator is more desirable for those commonly used coverage levels (e.g., nominal level>1% ). We illustrate these confidence interval construction methods with a real data set from a maternal congenital heart disease study.     

Numerical evaluation of tests based on different heteroskedasticity-consistent covariance matrix estimators

This article considers the issue of performing tests in linear heteroskedastic models when the test statistic employs a consistent variance estimator. Several different estimators are considered, namely: HC0, HC1, HC2, HC3, and their bias-adjusted versions. The numerical evaluation is performed using numerical integration methods; the Imhof algorithm is used to that end. The results show that bias-adjustment of variance estimators used to construct test statistics delivers more reliable tests when they are performed for the HC0 and HC1 estimators, but the same does not hold for the HC3 estimator. Overall, the most reliable test is the HC3-based one.     

Adaptive designs for single‐arm phase II trials in oncology

Clinical phase II trials in oncology are conducted to determine whether the activity of a new anticancer treatment is promising enough to merit further investigation. Two‐stage designs are commonly used for this situation to allow for early termination. Designs proposed in the literature so far have the common drawback that the sample sizes for the two stages have to be specified in the protocol and have to be adhered to strictly during the course of the trial. As a consequence, designs that allow a higher extent of flexibility are desirable. In this article, we propose a new adaptive method that allows an arbitrary modification of the sample size of the second stage using the results of the interim analysis or external information while controlling the type I error rate. If the sample size is not changed during the trial, the proposed design shows very similar characteristics to the optimal two‐stage design proposed by Chang et al. (Biometrics 1987; 43:865–874). However, the new design allows the use of mid‐course information for the planning of the second stage, thus meeting practical requirements when performing clinical phase II trials in oncology. Copyright © 2012 John Wiley & Sons, Ltd.     

Truncation invariant copulas and a testing procedure

ABSTRACT

The class of bivariate copulas that are invariant under truncation with respect to one variable is considered. A simulation algorithm for the members of the class and a novel construction method are presented. Moreover, inspired by a stochastic interpretation of the members of such a class, a procedure is suggested to check whether the dependence structure of a given data set is truncation invariant. The overall performance of the procedure has been illustrated on both simulated and real data.     

邓小平社会主义核心价值观教育思想探析

以泰州某大跨度连续梁桥的静动载试验为例，建立ANSYS和桥梁博士模型进行静动力有限元数值计算。将试验结果与模型计算值进行比较，试验结果表明,该桥结构刚度和承载能力满足设计要求。     

水驱砂岩油藏孔喉结构变化的三维网络模拟

以长期水驱实验为基础，建立了等效水驱砂岩储层孔喉结构变化的三维网络模拟模型，结合三维微粒运移机制和有限差分求解方法，得到了长期水驱砂岩油藏孔喉结构变化规律：（1） 冲刷后喉道半径呈增加趋势，喉道半径变化范围变大，极小喉道半径呈微弱减小趋势；（2） 孔隙网络模型中冲刷半径扩大的孔道分布形式与原始孔隙网络结构密切相关，并非所有的大孔道都串联起来贯穿岩芯孔隙网络的两个端面，但入口端和出口端部分大孔道相互连通，形成端面上的大孔道网络群。网络模拟注水结果结合采油井测试，可为注水剖面的调整提供更加可靠的依据。     

Unconditional analogues of Cochran–Mantel–Haenszel tests

The Cochran–Mantel–Haenszel tests are a suite of tests that are usually defined as conditional tests, tests that assume all marginal totals are known before sighting the data. Here unconditional analogues of these tests are defined for the more usual situation when the marginal totals are not known before sighting the data.     

孔子传播思想研究

孔子的传播理念是"和而不同",即"仁"与"礼"的统一。就人际传播而言,"仁"这一概念的提出为平等传播关系的建立提出了理论依据。孔子的传播思想博大精深,包罗万象,涉及传播符号、传播目的、受众思想、舆论思想、传播环境等诸多方面。其对传播符号的论述涉及传播符号的划分、语言的遮蔽性、语言的工具性、传播符号的规范、语言表达的有限性和无限性、形式与内容等方面;其传播目的论带有很强的实践理性色彩,认为传播的目的在于由"学"而"习",在于"言"和"行"的统一;风草论是孔子受众思想的重要方面,他一方面认为君子对民众的教化恰如风过草偃,效果明显,另一方面又认为传播威力虽然巨大,但也有一定限度,取得理想的传播效果非一日之功,这比"魔弹论"更加客观;历史传播方面,他认识到"载之空言"和"见之于行事"两种传播方式迥异的传播效果,发明了"托古立言"的传播方式;他还强调在舆论与独立思考之间加以平衡,既重视舆论又不盲从。