Confidence interval estimation of the difference between paired AUCs based on combined biomarkers

In many diagnostic studies, multiple diagnostic tests are performed on each subject or multiple disease markers are available. Commonly, the information should be combined to improve the diagnostic accuracy. We consider the problem of comparing the discriminatory abilities between two groups of biomarkers. Specifically, this article focuses on confidence interval estimation of the difference between paired AUCs based on optimally combined markers under the assumption of multivariate normality. Simulation studies demonstrate that the proposed generalized variable approach provides confidence intervals with satisfying coverage probabilities at finite sample sizes. The proposed method can also easily provide P-values for hypothesis testing. Application to analysis of a subset of data from a study on coronary heart disease illustrates the utility of the method in practice.     

论国民文明行为的缺失及对策

提高国民的文明行为水平是提高国民素质、建设社会主义精神文明的基础,是落实科学发展观、构建和谐社会的重要保证。影响国民文明行为的原因是多方面的,要改变这一现状必须结合中国现代化建设的实际情况,采取有效的方法、措施,进一步引导国民形成良好的文明行为习惯,为构建和谐社会铺平道路。     

资助低收入学生就读高等教育：美国的经验

资助低收入学生就读高等教育 ,是世界各国都十分重视的一项公共政策。美国在实施学生资助过程中 ,规定了低收入学生、财政需求、就学价格、家庭预期贡献等重要概念的标准和计算办法。受多种资助理念影响 ,美国学生资助是一种典型的多元混合资助模式 ,政府、高校、社会等机构通过奖学金、助学金、贷学金、工读计划等方式资助低收入学生。这种模式对于维系美国多元庞大的高等教育体系具有十分重要的意义     

藏医脉诊“冲、甘、恰”实质的探讨

藏医脉诊中“冲、甘、恰”的来源是一个历史悬案。这个复合名词究竟是指医生的食指、中指和无名指的古代名称,还是指脉诊中病人腕部动脉的3个诊脉部位,对此历代多有争论。从藏医古代经典《月王药诊》、《四部医典》开始就已存在“冲、甘、恰”与3个指头混称、定义含混的情况,这是后世争论的根源。在与中医脉诊的“寸、关、尺”的关系问题上学界的看法也有分歧。文章从医学发展史和文献学的角度进行分析,并从音韵学的角度进行剖析,认为藏医脉诊“冲、甘、恰”是中医脉诊“寸、关、尺”的转音,是指腕部诊脉的3个部位。     

生态人类学的理论源流及其后现代特征

生态人类学是文化人类学的一门新兴的分支学科,已成为西方当代文化人类学的重要流派,并对文化人类学的发展产生了很大影响。生态人类学的不同流派以不同形式反映了“环境决定论”的基本思想,对人类中心主义、科学主义和理性主义等现代性的批判表现出明显的后现代主义思想特征。     

试论民族地区普通中学多媒体课件制作及管理

运用现代教育技术提高教学效率是民族地区普通中学发展的必由之路。只有正确认识民族地区普通中学教育技术应用的背景,加强对此类教学资源的管理,才能使之更好服务于教学,提高民族地区教学实践活动的效率。     

"走西口"与晋陕内蒙古毗连带民歌圈的生成

晋西北山曲、陕北信天游、内蒙古原绥远地区的爬山歌 ,体例相同 ,词曲相近 ,共同构成我国北方单独的一个民歌圈 ,其生成与清代民国时期的“走西口”移民运动密切相关。在“走西口”过程中 ,晋西北、陕北人口大批向河套及大青山前后地区移居 ,形成以山西河曲、保德人和陕西府谷、神木、榆林人为核心的“河府移民圈” ,人口同源支持了民歌共性。长盛不衰的雁行式“走西口”生活 ,不断刺激着民歌的创造与发达 ,使三地民歌的交汇共生走向高潮 ,在发展中推动了三地民歌的同质化过程。     

文化的多元性与少数民族双语教学

现代化是每个民族繁荣昌盛的必由之路,丧失现代化意味着民族的贫困;每个民族又应保在自己的优秀文化传统,丧失文化传统意味着民族的消亡。民族教育中正确处理好现代化与传统文化的关系,就要做到民族教育的现代化和现代教育的现代化。文章结合两个藏汉双语教学的典型实践,从文化的多元性角度,引发了对民族教育中双语教学问题的思考。     

Mixed-effects Models with Skewed Distributions for Time-varying Decay Rate in HIV Dynamics

After initiation of treatment, HIV viral load has multiphasic changes, which indicates that the viral decay rate is a time-varying process. Mixed-effects models with different time-varying decay rate functions have been proposed in literature. However, there are two unresolved critical issues: (i) it is not clear which model is more appropriate for practical use, and (ii) the model random errors are commonly assumed to follow a normal distribution, which may be unrealistic and can obscure important features of within- and among-subject variations. Because asymmetry of HIV viral load data is still noticeable even after transformation, it is important to use a more general distribution family that enables the unrealistic normal assumption to be relaxed. We developed skew-elliptical (SE) Bayesian mixed-effects models by considering the model random errors to have an SE distribution. We compared the performance among five SE models that have different time-varying decay rate functions. For each model, we also contrasted the performance under different model random error assumptions such as normal, Student-t, skew-normal, or skew-t distribution. Two AIDS clinical trial datasets were used to illustrate the proposed models and methods. The results indicate that the model with a time-varying viral decay rate that has two exponential components is preferred. Among the four distribution assumptions, the skew-t and skew-normal models provided better fitting to the data than normal or Student-t model, suggesting that it is important to assume a model with a skewed distribution in order to achieve reasonable results when the data exhibit skewness.     

基于邻里汇模式的上海城市社区公共服务质量调研报告

"邻里汇"作为一种社区公共服务供给新模式,在公共服务领域有其独特的优势."邻里汇"汇集了养老、康复、助餐、助浴和社区生活服务等功能,成为社区居民休闲的汇聚地.要尽力争取让各年龄、各阶层的居民都能走出家门,一起加入"邻里汇"的大家庭中.有了社区居民的积极参与,才能将"邻里汇"建设成为促进社区和谐、满足多元需求的社区服务载体,营造出睦邻互助的良好氛围.