Assessing accuracy of a continuous screening test in the presence of verification bias

Summary.  In studies to assess the accuracy of a screening test, often definitive disease assessment is too invasive or expensive to be ascertained on all the study subjects. Although it may be more ethical or cost effective to ascertain the true disease status with a higher rate in study subjects where the screening test or additional information is suggestive of disease, estimates of accuracy can be biased in a study with such a design. This bias is known as verification bias. Verification bias correction methods that accommodate screening tests with binary or ordinal responses have been developed; however, no verification bias correction methods exist for tests with continuous results. We propose and compare imputation and reweighting bias-corrected estimators of true and false positive rates, receiver operating characteristic curves and area under the receiver operating characteristic curve for continuous tests. Distribution theory and simulation studies are used to compare the proposed estimators with respect to bias, relative efficiency and robustness to model misspecification. The bias correction estimators proposed are applied to data from a study of screening tests for neonatal hearing loss.     

Social Stratification and the Division of Household Labor in Japan: The Effect of Wives' Work on the Division of Labor among Dual-earner Families

Abstract:  This article explores the relationship between social stratification and the division of household labor by examining how the contribution to housework by husbands in dual-earner families varies across the Japanese social stratification structure. First, I review previous studies concerning the determinants of husbands' participation in housework and construct four hypotheses regarding the relative resources explanation, the time constraints explanation, the ideology/sex role explanation, and the alternative manpower explanation. Second, I examine the empirical support for these hypotheses in dual-earner couples and the effect of social stratification on husband's participation in housework, which has not been studied thus far. Third, I investigate the effect of social stratification in more detail. According to the results of TOBIT regressions and other supplementary analyses, the principal findings are as follows:

• 1) 

  the relative resources explanation is not supported;

       

综合实践活动课程实施的问题与对策

教师的课程理论素养较差,与综合实践活动课程实施的要求不相适应;综合实践活动课程的实施缺乏相关的制度保障和社会支持,是综合实践活动课程实施中存在的主要问题.解决问题的对策是:加强对教师的培训,提高教师实施综合实践活动课程的能力;完善学校相关教研、培训及管理等制度,为综合实践活动课程的实施提供制度保障;建立良好的社会支持和保障系统,充分利用各种资源,为综合实践活动课程的实施创造更好的条件.     

论休闲产业发展与社会的全面进步

随着我国全面建设小康社会目标的实施,休闲产业也因得到需求方面的拉动将进入快速发展时期。本文论述了休闲产业的内涵与特征,研究了休闲产业发展对社会发展的推动作用。     

我国高校办学经费不足的原因及对策探讨

本文浅议在市场经济条件下,我国高等教育在蓬勃发展的同时,高等学校办学经费所面临的主要问题,并通过分析提出解决这些问题的办法。     

社会转型与人际关系结构的变化--由情感型人际关系结构向理性型人际关系结构的转化

人们结成一定的人际关系结构是由人的需要决定的 ,而人的需要又可以简单地分为情感需要和理性需要 ,与此相应 ,人际关系结构可以分为情感型人际关系和理性型人际关系。在中国长期的传统社会里 ,由于受传统社会结构的影响 ,人际关系结构明显表现为以情感为核心 ,重情不重理是传统中国人行为的普遍逻辑。但是 ,当前我国正处于社会转型时期 ,社会结构正发生着急剧的变化 ,人际交往中理性成分日益增加 ,人际关系结构表现出由情感型人际关系结构向理性型人际关系结构变化的趋势 ,我们必须对此有着清醒的认识。     

通向可持续发展的社会（I）—可持续发展模式论

模式是对事物行为过程的摹写或可供模仿的模板 ,可持续发展社会模式是对人类社会可持续发展行为的摹写与确定的标准。可持续发展模式涉及到一大类模式体系 ,但它们有其统一的基本特征———共同性、持续性和公平性 ,满足同一的要求———经济性、福利性与和谐性。可持续发展模式包括社会组织、体制制度、经济、教育、空间结构等等。     

两相交流伺服电机动态性能的研究

对于两相交流电机的速度伺服系统,分析在幅值控制时系统的机械特性与调节特性,提出了影响两相交流伺服电机动态性能的因素是系统的机械时间常数及增益系数的变化。为了防止因机械时间常数及增益系数的变化而引起的动态特性变差,采用一种简易跟随模型参考自适应控制方法,通过模型与自适应机构的调节作用,改善两相交流伺服电机系统的动态特性和控制精度。计算机仿真结果表明,电机的动态持性良好。     

女性堕落文本的互补性阐释--《月牙儿》、《沉香屑·第一炉香》比较

老舍、张爱玲对故事中的母性堕落蓝本、女性堕落心路历程、母女两代人生存命运的不同处理，使得《月牙儿》与《沉香屑·第一炉香》这两篇小说构成了文本阐释的某种互补性。这种互补性主要表现在两位作家在对女性堕落、人性畸变的成因进行探讨时，对社会性因素、人性因素的不同侧重和对文化因素不同层面的观照上。     

知识型企业结构、特征及报酬递增效应分析

在市场经济条件下,知识已经成为企业竞争力的源泉.知识经济、知识管理、知识型企业等思想被越来越多的人所接受.和传统企业相比,知识型企业的结构及特征有它特定的一面.文章在分析知识型企业内外部结构的基础上,对知识型企业的特征进行了分析,进而探讨了由其特征所决定的知识型企业生产函数及报酬递增效应.