Evaluation of adjustments for partial non-response bias in the US National Immunization Survey

Summary.  Many health surveys conduct an initial household interview to obtain demographic information and then request permission to obtain detailed information on health outcomes from the respondent's health care providers. A 'complete response' results when both the demographic information and the detailed health outcome data are obtained. A 'partial response' results when the initial interview is complete but, for one reason or another, the detailed health outcome information is not obtained. If 'complete responders' differ from 'partial responders' and the proportion of partial responders in the sample is at least moderately large, statistics that use only data from complete responders may be severely biased. We refer to bias that is attributable to these differences as 'partial non-response' bias. In health surveys it is customary to adjust survey estimates to account for potential differences by employing adjustment cells and weighting to reduce bias from partial response. Before making these adjustments, it is important to ask whether an adjustment is expected to increase or decrease bias from partial non-response. After making these adjustments, an equally important question is 'How well does the method of adjustment work to reduce partial non-response bias?'. The paper describes methods for answering these questions. Data from the US National Immunization Survey are used to illustrate the methods.     

MTEMcell中场的均匀性分析

利用直线法对具有任意宽度芯板的变形横电磁波小室（ＭＴＥＭｃｅｌｌ）进行了分析，得出了电场分布的计算公式。根据数值计算结果，讨论了ＭＴＥＭｃｅｌｌ中场分布的均匀性，并计算了特性阻抗。     

非平衡非均匀业务与ATM交换性能

研究了非平衡与非均匀业务对于输出缓冲型ATM交换系统性能的影响,分析表明输入业务的非平衡性对交换性能无影响,但非均匀性却有着严重的影响,计算机模拟证实了理论分析所得出的结论。     

Measurements of separation among probability densities or random variables

Distance between two probability densities or two random variables is a well established concept in statistics. The present paper considers generalizations of distances to separation measurements for three or more elements in a function space. Geometric intuition and examples from hypothesis testing suggest lower and upper bounds for such measurements in terms of pairwise distances; but also in L_p spaces some useful non-pairwise separation measurements always lie within these bounds. Examples of such separation measurements are the Bayes probability of correct classification among several arbitrary distributions, and the expected range among several random variables.     

论新媒体背景下马克思主义的有效传播

以互联网为代表的第四媒体和以手机为代表的第五媒体等新媒体的强势发展,正在引领着新的信息革命,也改变着信息传播的环境和方式.马克思主义要在新媒体发展的背景下,利用新技术,做好与传统媒体、与人际传播的融合,从而使得相关马克思主义的信息交流更为社会化,实现有效传播,更易被广大人民群众所接受.     

非政府组织成员消极行为的扩散及应对策略——基于社会网络的分析

非政府组织的非政府性、志愿性等特征决定了其成员行为的选择,在很大程度上取决于成员间的关系与互动。当环境和个人因素对消极行为扩散具有较弱的约束时,通过社会网络视角来分析成员消极行为的扩散最有预见性。基于社会网络理论,构建出非政府组织成员消极行为扩散综合模型。要预防消极行为的扩散,就应从非政府组织成员的社会网络入手。     

评诺贝尔医学奖获得者科塞尔发现细胞化学结构的思维方法

在科学研究的道路上，科塞尔之所以发现细胞的化学结构，全得益于否证思维用得好。他用细胞核内外同样存在核素，核酸是核蛋白的辅基，碱性二氨基酸组成蛋白质，核蛋是蛋白质的中心理论，辩证地否定了米斯彻形而上学核素论。至今他的理论仍是正确的。     

统一建模语言UML分层抽象建模机制(英文)

在总结传统软件开发方法经验的基础上，严格遵守软件开发方法原则，从UML建模思想出发，对传统UML三层抽象建模结构进行了分析，并引入“抽象”和“分解”作为UML建模的核心思想；提出了UML分层抽象建模机制的构想，将计算机系统开发过程概括为对功能信元、结构信元、关联信元、实现信元和集成信元的提取过程，并以此作为UML建模的指导。有效了利用UML完整语义定义，克服了传统面向对象开发方法的缺陷，实现了建模过程从需求到分析的过渡以及功能和实现事实上的分离。     

Athletes’ Perceptions of National Collegiate Athletic Association–Mandated Sickle Cell Trait Screening: Insight for Academic Institutions and College Health Professionals

Abstract

Objective: The study objective was to explore athletes’ perspectives of National Collegiate Athletic Association (NCAA)–mandated sickle cell trait (SCT)–screening policy by examining race- and gender-related differences in athletes’ perceptions regarding risk of having SCT and concern about loss of playing time. Participants: Participants were 259 athletes at a southeastern United States campus during April–August of 2010. Methods: Athletes completed a 21-question survey. Results: The majority of athletes (81.7%) perceived that they would have a high level of concern if found to carry the SCT. African Americans were 9.07 times more likely than Caucasians to perceive risk of having the SCT. The majority of athletes disagreed (38.4%) or did not know (50.8%) if they would lose playing time related to carrying the SCT. Conclusion: Campus health professionals must be aware of athletes’ perspectives on NCAA's SCT screening so that athletes are not unnecessarily subjected to stress or harm.     

产业集群多层次网络结构对集群风险扩散的影响

文章分析了产业集群网络结构对集群的风险抵御能力的影响机理。利用温州鞋革业集群、东莞玩具业集群、硅谷和128公路区集群等案例对该影响机理进行了论证,并运用仿真模拟方法构建了集群结构模型,刻画了在外生性风险和内生性风险的扩散过程中集群结构的动态演化。主要结论有:马歇尔集群网络具有无标度网络和小世界网络的拓扑结构属性,轮轴式集群网络具有接近无标度网络极限状态的结构属性;两类集群对外生性风险扩散的抗性显著高于其对内生性风险扩散的抗性;马歇尔集群对内生性风险的抵御能力优于轮轴式集群,而轮轴式集群对外生性风险抗性则相对较强。