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61.
以756名中学生为研究对象,对学业投入、学业成就、同伴团体进行追踪测量,探讨青少年同伴团体的学业投入及学业成就是否存在同伴选择与同伴影响效应。结果表明:(1)在1年的追踪时间中,青少年学业投入的发展呈下降趋势,初始水平与下降速度负相关,学业成就的发展呈上升趋势,初始水平与上升速度无显著相关;(2)学业投入与学业成就存在同伴选择效应,青少年倾向选择与自己学业投入及学业成就相似的个体构建同伴团体;(3)青少年的学业投入及学业成就与同伴逐渐趋近相似,即同伴影响效应显著。  相似文献   
62.
Factor analysis is regularly used for analyzing survey data. Missing data, data with outliers and consequently nonnormal data are very common for data obtained through questionnaires. Based on covariance matrix estimates for such nonstandard samples, a unified approach for factor analysis is developed. By generalizing the approach of maximum likelihood under constraints, statistical properties of the estimates for factor loadings and error variances are obtained. A rescaled Bartlett-corrected statistic is proposed for evaluating the number of factors. Equivariance and invariance of parameter estimates and their standard errors for canonical, varimax, and normalized varimax rotations are discussed. Numerical results illustrate the sensitivity of classical methods and advantages of the proposed procedures.This project was supported by a University of North Texas Faculty Research Grant, Grant #R49/CCR610528 for Disease Control and Prevention from the National Center for Injury Prevention and Control, and Grant DA01070 from the National Institute on Drug Abuse. The results do not necessarily represent the official view of the funding agencies. The authors are grateful to three reviewers for suggestions that improved the presentation of this paper.  相似文献   
63.
While the intracarotid amobarbital procedure (IAP) was originally utilized to lateralize speech functions as an aid in the surgical treatment of epilepsy, additional uses for the IAP have emerged including: (1) the use of the IAP to predict post-surgical memory changes, including both global amnesia and smaller, yet significant, material-specific memory deficits; (2) the use of the IAP to provide confirmatory evidence of lateralization of seizure focus; and (3) the use of the IAP to predict post-surgical relief from seizures. While the literature on the IAP is extensive and growing, its utility is marred by the wide variability associated with the procedure itself from epilepsy center to center. This variability renders comparisons among IAP studies problematic and conclusions about IAP efficacy difficult. The variability associated with the amobarbital procedures, as well as the reliability and the validity of the IAP in its nonlanguage uses is reviewed here. A special emphasis is devoted to research conducted in the last decade. Also discussed is the future of the IAP including anticipated research directions.  相似文献   
64.
In the bioethical literature, discrimination in insurance on the basis of genetic risk factors detected by genetic testing has been defended and opposed on various ethical grounds. One important argument in favour of the practice is offered by those who believe that it is not possible to distinguish between genetic and non-genetic information, at least not for practical policy purposes such as insurance decision-making. According to the argument from indistinguishability, the use of genetic test information for insurance purposes should be permitted, because genetic test information is no different from non-genetic medical information in any relevant respect, therefore it would be inconsistent to prohibit the former whilst permitting the latter. This paper discusses and defends this argument and suggests a new, more tenable foundation.  相似文献   
65.
中小学生认知能力发展水平测验的研究   总被引:4,自引:0,他引:4  
以皮亚杰的认知发展理论为基础,采用皮亚杰及其学生研究认知发展时的任务为测验题目,编制成测量中小学生认知能力发展水平的测验.通过对2240名中小学生施测,结果表明本测验不仅具有很好的信度和效度,而且也具有适中的难度.然后以一所中学特长班学生为被试,通过对他们进行测量,并将测验结果与同年级普通班学生的认知成绩进行比较,结果存在很明显的差异.最后对中小学生认知能力发展水平测量问题进行了探讨.  相似文献   
66.
Two new tests for a model for the response times on pure speed tests by Rasch (1960) are proposed. The model is based on the assumption that the test response times are approximately gamma distributed, with known index parameters and unknown rate parameters. The rate parameters are decomposed in a subject ability parameter and a test difficulty parameter. By treating the ability as a gamma distributed random variable, maximum marginal likelihood (MML) estimators for the test difficulty parameters and the parameters of the ability distribution are easily derived. Also the model tests proposed here pertain to the framework of MML. Two tests or modification indices are proposed. The first one is focused on the assumption of local stochastic independence, the second one on the assumption of the test characteristic functions. The tests are based on Lagrange multiplier statistics, and can therefore be computed using the parameter estimates under the null model. Therefore, model violations for all items and pairs of items can be assessed as a by-product of one single estimation run. Power studies and applications to real data are included as numerical examples.  相似文献   
67.
The aim of this study is to understand adolescent players' satisfaction as a function of parenting styles, players' achievement strategies, and their norm breaking behavior. Finnish 14- and 16-year-old ice-hockey players (n=1018) completed a questionnaire measuring their achievement strategies (SAQ; Nurmi, Salmela--Aro & Haavisto, 1995 b), as well as scales of norm breaking and satisfaction, prepared for the present study. The parents (n=979) filled in scales measuring their parenting styles (CRPR; Pulkkinen, 1996) and attitudes towards norm breaking. Results revealed that players from authoritative families who showed a high level of mastery-orientation expressed high satisfaction in playing ice hockey. Results also showed negative associations between authoritative parenting and both task irrelevant and norm breaking behavior. Parents with parental stress and those with authoritarian parenting styles showed positive attitudes to norm breaking behavior, and players from authoritarian and parental stress homes showed norm breaking behavior in ice hockey. There was no association between norm breaking behavior and player satisfaction. Our results contribute to the planning of a coaching system that serves more educational and developmental purposes, and that encourages the desire to play ice hockey as a hobby.  相似文献   
68.
This paper reported two studies investigating high school students’ academic self-schemas in learning mathematics and their self-congruent learning engagement patterns. Using cluster analyses, Study 1 located two contrasting groups of students holding positive and negative self-schemas in learning mathematics among Chinese participants. MANOVA analyses showed that these two groups of Chinese schematic students differed from each other in the use of achievement goals, approaches to learning, and expected levels of performance. These findings were validated and extended in Study 2 using a culturally different sample, Australian students. Again, cluster analyses successfully classified Australian participants into positive and negative schematic clusters. It was also found that these two groups of schematic students approached learning mathematics in a self-congruent manner similar to those found in Study 1. The converging results in both studies lent empirical support to the theoretical formulation of positive and negative schematic students and the validity of using the self-schema concept to investigate motivation and learning. The differences in their learning engagement patterns were discussed in terms of students’ different academic self-schemas in learning mathematics.  相似文献   
69.
小学生心理素质与学业成绩的关系   总被引:8,自引:0,他引:8       下载免费PDF全文
运用《瑞文标准推理测验》和自编的《小学生心理素质问卷》对1247名小学生作心理素质团体测试。利用方差分析和聚类分析,探讨小学生心理素质与学业成绩的关系。结果表明:(1)总体上,学业成绩高分组心理素质优于学业成绩中等组和低分组,学业成绩中等组优于学业成绩低分组。(2)分年级看,不同年级不同学业成绩组的小学生在心理素质因素上的差异有不同。(3)学业成绩高分组学生主要分布在心理素质较好的水平层次,学业成绩中等组主要分布在心理素质中等水平层次上,而学业成绩低分组主要分布在心理素质不好的水平层次。  相似文献   
70.
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