Using biweight m-estimates in the two-sample problem part 1: symmetric populations

We propose replacing the usual Student's-t statistic, which tests for equality of means of two distributions and is used to construct a confidence interval for the difference, by a biweight-“t” statistic. The biweight-“t” is a ratio of the difference of the biweight estimates of location from the two samples to an estimate of the standard error of this difference. Three forms of the denominator are evaluated: weighted variance estimates using both pooled and unpooled scale estimates, and unweighted variance estimates using an unpooled scale estimate. Monte Carlo simulations reveal that resulting confidence intervals are highly efficient on moderate sample sizes, and that nominal levels are nearly attained, even when considering extreme percentage points.     

900 t轮胎式提梁机吊杆的有限元分析

900 t轮胎式提梁机是为高速铁路施工而开发的新机型。其主要功能是在预制梁场内对混凝土箱梁进行起吊、搬运和配合运梁车进行装车；其具有性能稳定、高效、功能集成化高的特点。主要介绍900 t轮胎式提梁机吊杆在吊运过程中的主要受力情况及在不同工况情况下的受力分析，根据最不利的工况进行有限元分析，分析结果跟实际应用中探伤结果进行比较，发现设计的吊杆可以满足1 000次吊装，并且改进延长探伤时间为加工吊杆提供优化的设计方案。     

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。     

Robust transformation mixed‐effects models for longitudinal continuous proportional data

The authors propose a robust transformation linear mixed‐effects model for longitudinal continuous proportional data when some of the subjects exhibit outlying trajectories over time. It becomes troublesome when including or excluding such subjects in the data analysis results in different statistical conclusions. To robustify the longitudinal analysis using the mixed‐effects model, they utilize the multivariate t distribution for random effects or/and error terms. Estimation and inference in the proposed model are established and illustrated by a real data example from an ophthalmology study. Simulation studies show a substantial robustness gain by the proposed model in comparison to the mixed‐effects model based on Aitchison's logit‐normal approach. As a result, the data analysis benefits from the robustness of making consistent conclusions in the presence of influential outliers. The Canadian Journal of Statistics © 2009 Statistical Society of Canada     

二元家庭暴力证明标准初探

传统严苛的家庭暴力证明标准和立法改革中过于宽松的家庭暴力证明标准尚有缺失存在,而要在家庭暴力民事认定上实现"受害人"与"施暴人"在利益上的衡平,建议采用二元家暴证明标准。依据二元家暴证明标准,对于作为离婚理由的家庭暴力认定采用相对宽松的证明标准,而对于作为离婚损害赔偿理由的家庭暴力认定则采用相对严格的证明标准。     

African-American Lesbian Identity Management and Identity Development in the Context of Family and Community

Don't Ask, Don't Tell is gaining attention in family studies literature as a cultural specific context to understand lesbian, gay, and bisexual visibility in African-American families and communities. This policy suggests that sexual minorities are accepted within African-American families and communities as long as they do not label themselves or acknowledge publicly that they engage in same-sex relationships. The narratives of two African-American lesbians (aged 26 and 27 years) are chronicled in the present study to reveal their lesbian identity development, lesbian identity management, and how they defined and navigated Don't Ask, Don't Tell. They encountered challenges and successes in a quest to find communities that would embrace and affirm their multiple marginalized identities. Their stories are offered as a point of entry to further inquiry concerning African-American lesbian visibility and identity proclamation within African-American families and communities.     

关于研究与开发费用的会计处理

研究与开发费用在会计上的处理主要有三种方法,一是完全费用化,二是完全资本化,三是部分费用化,造成这些处理方法不同的主要原因之一,是对研究与开发费用的范围与效用理解不同.本文在对我国研究与开发费用科学分析的基础上,提出了对此费用会计处理的新的见解.     

浅论高校档案信息服务的创新

高校档案信息是重要的经济资源 ,具有价值性、时效性和可传输性的特征。加强高校档案信息服务 ,必须从观念、工作制度和工作方式三方面进行创新。     

Comparisons of the percentage points of distributions with the same first four moments,chosen from eight different systems of frequency curves

Probability integrals and percentage points of univariate distributions from up to eight different families, having common first four moments are compared. Among interesting observations is the remarkable consistency in the standardized upper and lower 5% points over considerable regions of the √β₁, β₂ plane; also the closeness of agreement between the log-normal and non-central t distributions and the Pearson Type VI and Type IV curves respectively.     

The two-sample Winsorized t

This paper extends the single-sample Winsorized t to the case of two independent samples. Statistics are defined for both the cases of equal and unequal population variances. Monte Carlo techniques were used to find the approximate distributions of these statistics as well as to evaluate their performances in comparison to the trimmed t . It was found that as far as the power is concerned, the differences between the Winsorized t and the trimmed t are so small that the choice is immaterial for practical purposes.