P-value adjustment for multiple binary endpoints

The p-value-based adjustment of individual endpoints and the global test for an overall inference are the two general approaches for the analysis of multiple endpoints. Statistical procedures developed for testing multivariate outcomes often assume that the multivariate endpoints are either independent or normally distributed. This paper presents a general approach for the analysis of multivariate binary data under the framework of generalized linear models. The generalized estimating equations (GEE) approach is applied to estimate the correlation matrix of the test statistics using the identity and exchangeable working correlation matrices with the model-based as well as robust estimators. The objectives of the approaches are the adjustment of p-values of individual endpoints to identify the affected endpoints as well as the global test of an overall effect. A Monte Carlo simulation was conducted to evaluate the overall family wise error (FWE) rates of the single-step down p-value adjustment approach from two adjustment methods to three global test statistics. The p-value adjustment approach seems to control the FWE better than the global approach Applications of the proposed methods are illustrated by analyzing a carcinogenicity experiment designed to study the dose response trend for 10 tumor sites, and a developmental toxicity experiment with three malformation types: external, visceral, and skeletal.     

浅议能人机制

能人就是在市场经济竞争中能够搏风击浪,取得优胜,为社会主义的物质文明和精神文明建设做出较大贡献的人.我们应当借鉴深圳经验,加大对能人的发现、培养、保护和使用力度,建立起能人辈出的机制.     

对称保正型h-变换的几个性质

通过对称保正型（ε，D（ε））h-变换的暂留性、常返性和不可约性的讨论，证明了对称保正型的暂留性、常返性和不可约性在h-变换下是不变的，由此得到（ε，D（ε））h-结合的m-胎紧m-特殊标准马氏过程的相应性质。     

大数幂剩余的二进制冗余数Montgomery算法

介绍了大数幂剩余的Montgomery算法,提出了基于二进制冗余数的大数幂剩余Montgomery算法模型。理论分析表明,采用二进制冗余数可减少乘法的进位传播,同时使算法的迭代步数减少17.2%。进一步提高了大数幂剩余的运算速度。     

CET阅读理解题:问题与方法(二)

本文通过对CET阅读理解考题、提问(问题)以及原文和提问中一些关键词语之间的内含百分比进行分析和对比,探索如何准确解题的方法与捷径。     

Welfare Rigidity,the Composition of Public Expenditure and the Welfare Trap

Welfare expenditure is characterized by rigidity, i.e., it goes up easily but is very hard to get down. We introduced welfare rigidity into an endogenous growth model that includes government expenditure to analyze the impact of welfare rigidity and the composition of public expenditure on economic growth and family utility. Our findings show that welfare spending and economic growth have a non-monotonic relationship that is negative or inverted U-shaped depending on cross-country differences. Higher welfare rigidity reduces long-term economic growth and household utility. According to the estimated optimal size of welfare expenditure, China, as a developing country with a large population, has to do all it can to improve people’s livelihood but must at the same time weigh its limited resources so that its welfare expenditure does not fall into a “welfare trap.”     

Risk minimization for an insurer with investment and reinsurance via g-expectation

Abstract

This paper is devoted to the study of a risk-based optimal investment and proportional reinsurance problem. The surplus process of the insurer and the risky asset process in the financial market are assumed to be general jump-diffusion processes. We use a convex risk measure generated by g-expectation to describe the risk of the terminal wealth with investment and reinsurance. Under the aim of minimizing the risk, the problem is solved by using techniques of stochastic maximum principles. Two interesting special cases are studied and the explicit expressions for optimal strategies and corresponding minimal risks are derived.     

Relational and Overt Aggression in Childhood and Adolescence: Clarifying Mean‐level Gender Differences and Associations with Peer Acceptance

Research on relational aggression has drawn attention to how girls may be likely to aggress, but the role of gender is not fully understood. There are opposing views regarding whether relational aggression is most common among girls. Current findings demonstrate that when gender differences in relational aggression are assessed with peer nominations, gender differences favoring girls are more likely: (1) in adolescence than childhood; and (2) when statistical overlap with overt aggression is controlled. Results also indicated that associations of relational aggression with peer acceptance depend on the aggressor's gender, the peer rater's gender, and whether overlap with overt aggression is controlled. Associations of relational aggression with lower acceptance became non‐significant when overt aggression was controlled, suggesting that relational aggression displayed in isolation may not damage acceptance. In fact, in mid‐adolescence, girls’ relational aggression predicted greater liking by boys. Reducing relational aggression among adolescent girls may be especially challenging if the behavior is linked with acceptance by boys.     

Reporting cumulative proportion of subjects with an adverse event based on data from multiple studies

Experience has shown us that when data are pooled from multiple studies to create an integrated summary, an analysis based on naïvely‐pooled data is vulnerable to the mischief of Simpson's Paradox. Using the proportions of patients with a target adverse event (AE) as an example, we demonstrate the Paradox's effect on both the comparison and the estimation of the proportions. While meta analytic approaches have been recommended and increasingly used for comparing safety data between treatments, reporting proportions of subjects experiencing a target AE based on data from multiple studies has received little attention. In this paper, we suggest two possible approaches to report these cumulative proportions. In addition, we urge that regulatory guidelines on reporting such proportions be established so that risks can be communicated in a scientifically defensible and balanced manner. Copyright © 2010 John Wiley & Sons, Ltd.     

海尔集团基于网络营销导向的网站建设研究

以海尔集团为例，从网络营销的角度对大中型企业电子商务网站的相关问题进行研究。对海尔网站的各部分要素进行了详尽的分析，对海尔网站的网络设计优化进行了诊断，从中发现海尔网站的成功与不足之处，并进而揭示出我国大中型企业在此方面存在的共性问题，旨在使各大中型企业加深对网络营销导向的企业网站建设的认识，并为正在进行网络营销导向的网站建设的各大中型企业提供一定的参考与借鉴。