加强人大常委会监督应发挥机关协调、支持体系的作用

就人大常委会自身而言,加强其依法行使监督权的途径可通过科学运用各种监督形式、完善监督权相关制度两种方式实现,然任何制度的顺利运行仅依靠自身改善难以万全,只有在完善自身的基础上充分结合其他社会资源方能内外兼修,从而形成完善体系。本文作为项目阶段性成果,以专门委员会、工作机构和专家顾问三方面力量为切入点,论述如何建立和发挥机关协调、支持体系的作用,从而实现加强人大常委会依法行使监督权的目的。     

信息化背景下发展型农村地区手机使用人群分化研究——基于晋南村庄的实证调查

随着农村信息化的迅猛发展和手机迅速的普及,手机使用逐渐进入人们的学习、工作和生活之中,改变着人们的思维和行为方式,打破传统人群基于人缘、血缘、地缘、为纽带的人群共同成员感和归属感,进而导致农村地区人群也在走向分化。以晋南村庄的手机使用情况的实地调查数据为依托,采用定性和定量的分析方法,从体制依存和自我依存的两个角度进行分析把握,结果表明,在信息化背景下的手机使用过程使得村庄人群存在明显的分化。结合以上分析,对这种现象进行了初步的了解和掌握,进而探讨这种现象对社会带来的价值与意义。     

土家族转用汉语及土家语濒危的成因

土家族转用汉语及土家语濒危的成因是多方面的。各种社会文化因素和语言因素构成了一个相互交织、相互关联、相互制约的复杂系统。但相对于语言因素的影响而言,社会文化因素的影响是主要的。其中社会变迁、政治、经济、文化、教育因素的影响起了决定性的作用。土家族与中原汉族地区长期的政治、军事、文化接触,经济活动方式的革新以及土汉杂居的环境,扩大了土家族对汉语的需求;汉学教育的实施和普及、开放的语言文化观念加速了土家族转用汉语的进程。归根结底,土家族语言价值取向的转变及其语言选择行为是对其社会经济文化变迁的积极回应。     

鹅湖之会与稼轩词派

辛弃疾、陈亮二人的鹅湖之会是辛、陈交往的一个重要事件,也是稼轩词派形成中的一个标志性的事件.在这次会面中,辛、陈二人以词相互酬答,为后世留下了一段难得的佳话,更在实际的意义上强化了稼轩词派的显性特征,扩充了稼轩词派的创作队伍,壮大了这一词派的创作力量,使得稼轩词派成为名副其实的一个流派.     

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.     

Operating Characteristics for Group Sequential Trials Monitored Under Fractional Brownian Motion

Brownian motion has been used to derive stopping boundaries for group sequential trials, however, when we observe dependent increment in the data, fractional Brownian motion is an alternative to be considered to model such data. In this article we compared expected sample sizes and stopping times for different stopping boundaries based on the power family alpha spending function under various values of Hurst coefficient. Results showed that the expected sample sizes and stopping times will decrease and power increases when the Hurst coefficient increases. With same Hurst coefficient, the closer the boundaries are to that of O'Brien-Fleming, the higher the expected sample sizes and stopping times are; however, power has a decreasing trend for values start from H = 0.6 (early analysis), 0.7 (equal space), 0.8 (late analysis). We also illustrate study design changes using results from the BHAT study.     

Group Variable Selection with Oracle Property by Weight-Fused Adaptive Elastic Net Model for Strongly Correlated Data

This paper is the generalization of weight-fused elastic net (Fu and Xu, 2012 Fu, G., Xu, Q. (2012). Grouping variable selection by weight fused elastic net for multi-collinear data. Communications in Statistics-Simulation and Computation 41(2):205–221.[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]), which performs group variable selection by combining weight-fused LASSO(wfLasso) and elastic net (Zou and Hastie, 2005 Zou, H., Hastie, T. (2005). Regularization and variable selection via the elastic net. Journal of the Royal Statistical Society: Series B (Statistical Methodology) 67(2):301–320.[Crossref], [Web of Science ®] , [Google Scholar]) penalties. In this study, the elastic net penalty is replaced by adaptive elastic net penalty (AdaEnet) (Zou and Zhang, 2009 Zou, H., Zhang, H. (2009). On the adaptive elastic-net with a diverging number of parameters. Annals of Statistics 37(4):1733–1751.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), and a new group variable selection algorithm with oracle property (Fan and Li, 2001 Fan, J., Li, R. (2001). Variable selection via nonconcave penalized likelihood and its oracle properties. Journal of the American Statistical Association 96(456):1348–1360.[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]; Zou, 2006 Zou, H. (2006). The adaptive lasso and its oracle properties. Journal of the American Statistical Association 101(476):1418–1429.[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) is obtained.     

Point estimation after early stopping in a repeated measures trial

When the individual measurements are statistically independent, the maximum likelihood estimator calculated at the end of a sequential procedure overestimates the underlying effect. There are many clinical trials in which we are interested in comparing changes in responses between two treatment groups sequentially. Lee and DeMets (1991, JASA 86, 757–762) proposed a group sequential method for comparing rates of change when a response variable is measured for eaeh patient at successive follow-up visits. They assumed that the response follows the linear mixed effects model and derived the asymptotic joint distribution of the sequentially computed statistics. In this article, we consider the maximum likelihood estimator (MLE), the median unbiased estimator (MUE) and the midpoint of a 100(1-α)% confidence interval as point estimators for the rate of change in the linear mixed effects model, and investigate their properties by Monte Carlo simulation.     

Estimation of the Proportion of Defective Units by Using Group Testing Under the Existence of a Threshold of Detection

Group testing procedures, in which groups containing several units are tested without testing each unit, are widely used as cost-effective procedures in estimating the proportion of defective units in a population. A problem arises when we apply these procedures to the detection of genetically modified organisms (GMOs), because the analytical instrument for detecting GMOs has a threshold of detection. If the group size (i.e., the number of units within a group) is large, the GMOs in a group are not detected due to the dilution even if the group contains one unit of GMOs. Thus, most people conventionally use a small group size (which we call conventional group size) so that they can surely detect the existence of defective units if at least one unit of GMOs is included in the group. However, we show that we can estimate the proportion of defective units for any group size even if a threshold of detection exists; the estimate of the proportion of defective units is easily obtained by using functions implemented in a spreadsheet. Then, we show that the conventional group size is not always optimal in controlling a consumer's risk, because such a group size requires a larger number of groups for testing.     

Perceived group cohesion versus actual social structure: A study using social network analysis of egocentric Facebook networks

Research on group cohesion often relies on individual perceptions, which may not reflect the actual social structure of groups. This study draws on social network theory to examine the relationship between observable structural group characteristics and individual perceptions of group cohesion. Leveraging Facebook data, we extracted and partitioned the social networks of 109 participants into groups using a modularity algorithm. We then surveyed perceptions of cohesion, and computed group density and size using social network analysis. Out of six linear mixed effects models specified, a random intercept and fixed slope model with group size as a predictor of perceived group cohesion emerged as best fitting. Whereas group density was not linked to perceived cohesion, size had a small negative effect on perceived cohesion, suggesting that people perceive smaller groups as more cohesive. We discuss the potential of social network analysis, visualization tools, and Facebook data for advancing research on groups.