Smoothed bootstrap bandwidth selection for nonparametric hazard rate estimation

A smoothed bootstrap method is presented for the purpose of bandwidth selection in nonparametric hazard rate estimation for iid data. In this context, two new bootstrap bandwidth selectors are established based on the exact expression of the bootstrap version of the mean integrated squared error of some approximations of the kernel hazard rate estimator. This is very useful since Monte Carlo approximation is no longer needed for the implementation of the two bootstrap selectors. A simulation study is carried out in order to show the empirical performance of the new bootstrap bandwidths and to compare them with other existing selectors. The methods are illustrated by applying them to a diabetes data set.     

Need-service matching in substance abuse treatment: Racial/ethnic differences

This study examines the impact of ancillary health and social services matched to client needs in substance abuse treatment for African Americans, Latinos and Whites. The study uses data collected from 1992 to 1997 for the National Treatment Improvement Evaluation Study, a prospective cohort study of substance abuse treatment programs and their clients. The analytic sample consists of 3142 clients (1812 African Americans, 486 Latinos, 844 Whites) from 59 treatment facilities. Results show that racial/ethnic minorities are underserved compared to Whites in the substance abuse service system. Different racial/ethnic groups come into treatment with distinct needs and receive distinct services. Although groups respond differentially to service types, substance abuse counseling and matching services to needs is an effective strategy both for retaining clients in treatment and for reducing post-treatment substance use for African Americans and Whites. Receipt of access services was related to reduced post-treatment substance use for Latinos. Study findings are relevant to planning special services for African Americans and Latinos.     

高校青年教师离职问题思考

青年教师是高校教学工作未来的核心力量,由于自身特点和诸多外界因素,离职率一直居高不下,对学校正常教学、科研活动的开展带来了比较大的负面影响。本文对高校青年教师离职原因进行了分析,并提出了解决这个问题的思路。     

构建提升校园文化品位的牵引机制

高校校园文化建设是社会文化建设的重要组成部分,如何提升校园文化品位，更好地为高校和社会服务，是摆在我们面前的迫切问题。本文着眼于校园文化品位的提高，在大量工作实践的基础上，从审美、互动、窗口、学风等方面探求提升校园文化品位的牵引机制，以助于实现校园文化建设向更高水平迈进的目标。     

Sample size estimation for comparing rates of change in K-group repeated count outcomes

Sample size estimation for comparing the rates of change in two-arm repeated measurements has been investigated by many investigators. In contrast, the literature has paid relatively less attention to sample size estimation for studies with multi-arm repeated measurements where the design and data analysis can be more complex than two-arm trials. For continuous outcomes, Jung and Ahn (2004 Jung, S., Ahn, C. (2004). K-sample test and sample size calculation for comparing slopes in data with repeated measurements. Biometrical J. 46(5):554–564.[Crossref], [Web of Science ®] , [Google Scholar]) and Zhang and Ahn (2013 Zhang, S., Ahn, C. (2013). Sample size calculation for comparing time-averaged responses in k-group repeated measurement studies. Comput. Stat. Data Anal. 58:283–291.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) have presented sample size formulas to compare the rates of change and time-averaged responses in multi-arm trials, using the generalized estimating equation (GEE) approach. To our knowledge, there has been no corresponding development for multi-arm trials with count outcomes. We present a sample size formula for comparing the rates of change in multi-arm repeated count outcomes using the GEE approach that accommodates various correlation structures, missing data patterns, and unbalanced designs. We conduct simulation studies to assess the performance of the proposed sample size formula under a wide range of designing configurations. Simulation results suggest that empirical type I error and power are maintained close to their nominal levels. The proposed method is illustrated using an epileptic clinical trial example.     

Designing a multiple state repetitive group sampling plan based on the coefficient of variation

A multiple state repetitive group sampling (MSRGS) plan is developed on the basis of the coefficient of variation (CV) of the quality characteristic which follows a normal distribution with unknown mean and variance. The optimal plan parameters of the proposed plan are solved by a nonlinear optimization model, which satisfies the given producer's risk and consumer's risk at the same time and minimizes the average sample number required for inspection. The advantages of the proposed MSRGS plan over the existing sampling plans are discussed. Finally an example is given to illustrate the proposed plan.     

Sparse Bayesian variable selection in multinomial probit regression model with application to high-dimensional data classification

Here we consider a multinomial probit regression model where the number of variables substantially exceeds the sample size and only a subset of the available variables is associated with the response. Thus selecting a small number of relevant variables for classification has received a great deal of attention. Generally when the number of variables is substantial, sparsity-enforcing priors for the regression coefficients are called for on grounds of predictive generalization and computational ease. In this paper, we propose a sparse Bayesian variable selection method in multinomial probit regression model for multi-class classification. The performance of our proposed method is demonstrated with one simulated data and three well-known gene expression profiling data: breast cancer data, leukemia data, and small round blue-cell tumors. The results show that compared with other methods, our method is able to select the relevant variables and can obtain competitive classification accuracy with a small subset of relevant genes.     

转型期农村教育社会分层功能弱化的制度性因素

学校教育制度应该促进农村学生的向上社会流动,然而在我国社会转型过程中的教育制度以城市教育为中心,优先发展城市教育,以"市场能力"和学业成绩作为学校选拔规则,以及重点学校制度对农村学生获得高一级教育机会的制约,导致了对农村学生的"教育排斥"。教育制度的城市化、市场化、精英化取向是转型期农村教育社会分层功能弱化的制度性原因。将现阶段农村教育主要功能定位于促进农村学生城市化和社会地位升迁,确立教育制度的正义原则,实现对农村学生的"差异补偿"是解决这一问题的主要思路。     

我国产业结构变迁与城市化水平提升间互动关系研究

城市化作为二三产业发展在城市空间的动态物化载体,必然反映出区域特定时期社会经济发展的综合水平。我国产业结构演进与城市化进程之间存在着较密切的关联性,这种内在联系颇值得探讨。本文通过系统研究中国城市化进程与产业结构变迁、产业结构偏离度之间的关系,并着重剖析中国产业结构演进对城市化的弹性影响,最后从优化产业结构的维度提出推进新型城镇化发展战略的对策建议。     

日本共产党新党章透视

世纪之交,日共召开了22大,对有42年历史的党章进行了全面的修改,这在日共历 史上具有重要的意义,明确了日共在新世纪的方针政策和奋斗目标。现从修改党章的时代背 景、主要内容以及几点认识三个方面加以阐述。