有限群子群的几点结论

对有限群子群的刻划一直是有限群论的重要研究内容。我们在本文中利用群阶、群直积对有限群的子群作了些探讨，得到了几点结论。文中符号及术语均见。     

用分组神经网络识别手写体数字

用神经网络识别手写体数字,大多数采用的是单个的神经网络结构.本文给出一个基于特征输入的手写体数字识别的分组神经网络结构,它是一个混合网络(Hybrid System).实验的结果表明,同只采用单个神经网络结构的方法相比,分组网络具有更好的识别结果.     

关于有限群的超可解性

本文证明了定理1 设G为群,则W_∞(G)=SI(G) 定理2 设G为群,N■G,若G/N超可解且N的素数阶元均属于W_∞(G),则G超还解的充要条件是G与T_(2q)无关。     

An examination of factors contributing to a reduction in subgroup differences on a constructed-response paper-and-pencil test of scholastic achievement.

The authors investigated subgroup differences on a multiple-choice and constructed-response test of scholastic achievement in a sample of 197 African American and 258 White test takers. Although both groups had lower mean scores on the constructed-response test, the results showed a 39% reduction in subgroup differences compared with the multiple-choice test. The results demonstrate that the lower subgroup differences were explained by more favorable test perceptions for African Americans on the constructed-response test. In addition, the two test formats displayed comparable levels of criterion-related validity. The results suggest that the constructed-response test format may be a viable alternative to the traditional multiple-choice test format in efforts to simultaneously use valid predictors of performance and minimize subgroup differences in high-stakes testing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparing meta-analytic moderator estimation techniques under realistic conditions.

One of the most problematic issues in contemporary meta-analysis is the estimation and interpretation of moderating effects. Monte Carlo analyses are developed in this article that compare bivariate correlations, ordinary least squares and weighted least squares (WLS) multiple regression, and hierarchical subgroup (HS) analysis for assessing the influence of continuous moderators under conditions of multicollinearity and skewed distribution of study sample sizes (heteroscedasticity). The results show that only WLS is largely unaffected by multicollinearity and heteroscedasticity, whereas the other techniques are substantially weakened. Of note, HS, one of the most popular methods, typically provides the most inaccurate results, whereas WLS, one of the least popular methods, typically provides the most accurate results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

奇异元的几个特征

G是l-群,0相似文献   

格序群扭类A1

本文主要在扭类A与D之间找到了一种新的扭类A_1,并且证明了。A(?)A(?)D,及A(?)A~2,从而A~*=A~*=R~*。同时给出了A_1的一些性质及等价条件。     

1—群的互为上下子群及极大下子群

本文讨论了1-群的互为上下子群的性质以及极大下子群的唯一性,在非正规值的条件下给出了极大下子群的唯一表达形式,由此推广了R.N.Ball, P.Conradand M.Darnel在[1]中的结果。     

Varying forms of husband sexual aggression: Predictors and subgroup differences.

The relationships between two forms of husband sexual aggression (coercion and threatened/forced sex) and husband physical and psychological aggression were examined among a community sample of 164 couples. A stronger relationship between physical and sexual aggression was obtained than in previous research. Husbands' physical and psychological aggression predicted husbands' sexual coercion, but only physical aggression predicted threatened/forced sex. The more severely physically violent subtypes of the A. Holtzworth-Munroe et al. (2000) typology engaged in the most sexual coercion, and the most violent subtype (generally violent/antisocial) engaged in the most threatened/forced sex. In examining C. M. Monson and J. Langhinrichsen-Rohling's (1998) typology, the existence of a sexually violent-only subtype was documented, physically nonviolent husbands were found to engage in sexual coercion, and sexually and physically violent husbands engaged in the highest level of sexual aggression. The utility of using multiple measures, and both spouses' reports, to assess sexual aggression is emphasized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The postherapy period.

18 mo. after psychotherapy, a variety of tests were read-ministered to 69 available Ss constituting a biased subgroup from 93 tested previously at the beginning and at the termination of therapy. While the group as a whole showed no reliable movement after therapy, individuals made reliable and correlated changes. Only the Ss' direct report of such change was found to be predictable from several earlier measures. Less favorable movement was found on some measures for the 16 Ss who had additional therapy. While status at termination of therapy appears to be an adequate index of group effects associated with therapy, individuals show systematic trends in the subsequent 18 mo. (26 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)