东临碣石在绥中——《我从龙河走来》选载

读初中的时候就背诵过魏武帝曹操东临碣石,以观沧海这句脍炙人口的诗篇.那么,碣石究竟在哪里呢?我们到辽河流域采访时终于找到了答案: 碣石就在辽宁省绥中县.     

水与彩的魅力陈述——毛得墚画作印象

毛得墚(德良),1962年生人,辽宁省东港市人,1985年毕业于鲁迅美术学院美术教育系,中国美协会员、辽宁省美协理事、辽河画院专职画家。作品多次获奖,其中水彩画作《倾城乐》获第二届中国美术金彩奖,《瓷盘与干鱼》入选中国水彩百年画展,《苍宇永恒》获首届中国美术创作奖及第十一届全国美展优秀奖。多幅作品被中国美术馆和上海刘海粟美术馆等机构收藏。     

体验式教学理念下的英语语法习得应用研究

在英语作为外语的背景下是否应该教语法至今仍争论不休,但语法在语言学习中的作用勿容置疑.导致对语法教学的消极评价的原因是教学方法的使用和课堂活动的设计与呈现不当.中国环境下的英语语法规则内化,通过长期科学、合理、有趣的教学活动设计进行语法意识培养,从学得语法逐渐向习得语法转化,是可以实现的.体验式教学理念下的语法教学,调动学生积极参与语法体验,通过不同情景下的感知和合作互动达到成功体验的目标.     

日常思维历时态生成机制考评

始思维代表着人类日常思维的历史原型.原始思维在本质上是一种充满了集体表象的,互渗的、具体的、原逻辑思维,这些思维特征自然使原始人借助类比、隐喻、模拟等方法来理解周围的世界.从历时态来看,原始思维和日常思维之间具有先后相继的直接的内在契合性,虽然原始社会早已不复存在,但原始思维并没有因为原始社会的解体而消亡,它的许多规定性经过漫长农业文明仍以特殊的方式沉淀在日常思维中,由此构成了日常思维历时态生成的一条路径.     

Effects of unmeasured heterogeneity in the linear transformation model for censored data

We investigate the effect of unobserved heterogeneity in the context of the linear transformation model for censored survival data in the clinical trials setting. The unobserved heterogeneity is represented by a frailty term, with unknown distribution, in the linear transformation model. The bias of the estimate under the assumption of no unobserved heterogeneity when it truly is present is obtained. We also derive the asymptotic relative efficiency of the estimate of treatment effect under the incorrect assumption of no unobserved heterogeneity. Additionally we investigate the loss of power for clinical trials that are designed assuming the model without frailty when, in fact, the model with frailty is true. Numerical studies under a proportional odds model show that the loss of efficiency and the loss of power can be substantial when the heterogeneity, as embodied by a frailty, is ignored. An erratum to this article can be found at     

改进的投影寻踪分类模型及其在区域经济评价中的应用

作为多元数据的一种分析方法,投影寻踪分类模型已被一些研究者应用到实践中,并取得了良好的效果.然而,投影寻踪分类模型没有严格意义上的分类标准.通过引入有序样本聚类法,可以对投影寻踪分类模型得到的一维投影值进行客观分类.根据改进的模型,对江苏省区域经济的发展进行了综合评价,结果表明:改进的投影寻踪分类模型切实可行,为多元数据分类提供了新途径.     

机构投资者异质性的上市公司股利政策研究

 本文从现金股利政策的角度来研究机构投资者的投资行为和参与上市公司治理的情况。首先回顾了该方面的相关文献,以信号理论为基础,分析机构投资者与现金股利政策可能存在的关系;接着对机构投资者的基本特征以及我国机构投资者和上市公司现金股利政策的概况及特点进行了总结;最后本文以 2007至2010 年的机构投资者持股数据与上市公司现金股利政策数据进行统计分析、回归分析,实证检验了机构投资者异质性与上市公司股利政策之间的关系。     

An efficient sequential design of clinical trials

We propose an efficient group sequential monitoring rule for clinical trials. At each interim analysis both efficacy and futility are evaluated through a specified loss structure together with the predicted power. The proposed design is robust to a wide range of priors, and achieves the specified power with a saving of sample size compared to existing adaptive designs. A method is also proposed to obtain a reduced-bias estimator of treatment difference for the proposed design. The new approaches hold great potential for efficiently selecting a more effective treatment in comparative trials. Operating characteristics are evaluated and compared with other group sequential designs in empirical studies. An example is provided to illustrate the application of the method.     

Comparison of ANOVA-F and ANOM tests with regard to type I error rate and test power

A Monte Carlo simulation was conducted to compare the type I error rate and test power of the analysis of means (ANOM) test to the one-way analysis of variance F-test (ANOVA-F). Simulation results showed that as long as the homogeneity of the variance assumption was satisfied, regardless of the shape of the distribution, number of group and the combination of observations, both ANOVA-F and ANOM test have displayed similar type I error rates. However, both tests have been negatively affected from the heterogeneity of the variances. This case became more obvious when the variance ratios increased. The test power values of both tests changed with respect to the effect size (Δ), variance ratio and sample size combinations. As long as the variances are homogeneous, ANOVA-F and ANOM test have similar powers except unbalanced cases. Under unbalanced conditions, the ANOVA-F was observed to be powerful than the ANOM-test. On the other hand, an increase in total number of observations caused the power values of ANOVA-F and ANOM test approach to each other. The relations between effect size (Δ) and the variance ratios affected the test power, especially when the sample sizes are not equal. As ANOVA-F has become to be superior in some of the experimental conditions being considered, ANOM is superior in the others. However, generally, when the populations with large mean have larger variances as well, ANOM test has been seen to be superior. On the other hand, when the populations with large mean have small variances, generally, ANOVA-F has observed to be superior. The situation became clearer when the number of the groups is 4 or 5.     

Spatial Cluster Detection for Longitudinal Outcomes Using Administrative Regions

This article proposes a new spatial cluster detection method for longitudinal outcomes that detects neighborhoods and regions with elevated rates of disease while controlling for individual level confounders. The proposed method, CumResPerm, utilizes cumulative geographic residuals through a permutation test to detect potential clusters which are defined as sets of administrative regions, such as a town or group of administrative regions. Previous cluster detection methods are not able to incorporate individual level data including covariate adjustment, while still being able to define potential clusters using informative neighborhood or town boundaries. Often, it is of interest to detect such spatial clusters because individuals residing in a town may have similar environmental exposures or socioeconomic backgrounds due to administrative reasons, such as zoning laws. Therefore, these boundaries can be very informative and more relevant than arbitrary clusters such as the standard circle or square. Application of the CumResPerm method will be illustrated by the Home Allergens and Asthma prospective cohort study analyzing the relationship between area or neighborhood residence and repeated measured outcome, occurrence of wheeze in the last six months, while taking into account mobile locations.