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171.
Discretized multivariate normal structural models are often estimated using multistage estimation procedures. The asymptotic properties of parameter estimates, standard errors, and tests of structural restrictions on thresholds and polychoric correlations are well known. It was not clear how to assess the overall discrepancy between the contingency table and the model for these estimators. It is shown that the overall discrepancy can be decomposed into a distributional discrepancy and a structural discrepancy. A test of the overall model specification is proposed, as well as a test of the distributional specification (i.e., discretized multivariate normality). Also, the small sample performance of overall, distributional, and structural tests, as well as of parameter estimates and standard errors is investigated under conditions of correct model specification and also under mild structural and/or distributional misspecification. It is found that relatively small samples are needed for parameter estimates, standard errors, and structural tests. Larger samples are needed for the distributional and overall tests. Furthermore, parameter estimates, standard errors, and structural tests are surprisingly robust to distributional misspecification. This research was supported by the Department of Universities, Research and Information Society (DURSI) of the Catalan Government, and by grants BSO2000-0661 and BSO2003-08507 of the Spanish Ministry of Science and Technology.  相似文献   
172.
学习不良青少年与一般青少年学业情绪特点的比较研究   总被引:14,自引:0,他引:14  
俞国良  董妍 《心理科学》2006,29(4):811-814,818
本研究采用问卷法调查了1034名青少年(学习不良青少年506名),比较了学习不良青少年与一般青少年的学业情绪的特点。结果表明:(1)学习不良青少年的积极学业情绪显著低于一般青少年;学习不良青少年的消极学业情绪显著高于一般青少年。(2)学习不良青少年与一般青少年在学业情绪上的差异主要表现在初一、初二和高二、高三年级。(3)总体来说,男生的积极学业情绪多于女生,女生的消极学业情绪多于男生。  相似文献   
173.
One approach to encourage productive study strategies is to incorporate preparatory quizzes (or pre‐quizzes) in which students are required to submit answers to questions before the underlying material is covered in class. In the present study, students took an introductory mechanical engineering class that either included pre‐quizzes (treatment group) or did not (control group). Students in the treatment group visited the online textbook more often and earlier in advance of deadlines, indicating better management of their study time—behaviors that have been shown to be productive study strategies. They also performed better in the course, indicating that techniques intended to prime productive study strategies can pay off. Finally, measures of productive learning strategies correlated with measures of course performance for both groups. These findings support the pretesting principle, which holds that students study more effectively and learn better when they take practice tests before a lesson.  相似文献   
174.
Background/Objective: This study explored the association between active school travel (AST) and suicide attempts among adolescents in low- and middle-income countries (LMICs). Method: We used the data from the Global School-based Health Survey, including 127,097 adolescents aged 13-17 years from 34 LMICs. A self-reported survey was used to collect data on AST and suicide attempts as well as some variables. Multivariable logistic regression was performed to assess the association between AST and suicide attempts. A meta-analysis with random effects was undertaken to identify the difference in the association between AST and suicide attempts. Results: Across all the adolescents, the prevalence of AST was 37% and the prevalence of suicide attempts was 11.60%. Adolescents who engaged in AST were less likely to have suicide attempts irrespective of gender. The country-wise analysis indicated a large inconsistency in the association between AST and suicide attempt across the countries. Conclusions: AST would appear to be a protective factor for reducing suicide attempts among adolescents. However, the association between AST and suicide attempts varied greatly across the countries. Future studies should confirm the association between AST and suicide attempts.  相似文献   
175.
Background/Objective: The Dual Control Model suggests that sexual excitation and associated behaviors are the result of the balance between relatively independent excitatory and inhibitory mechanisms. Based on this theoretical model, the Sexual Excitation/Sexual Inhibition Inventory for Women (SESII-W) was developed to evaluate excitation and inhibition dimensions in women. The aim was to adapt and validate the SESII-W in the Spanish population. Method: A sample of 1,380 heterosexual women (aged 18 to 52) completed the Spanish SESII-W, together with other related instruments. After the translation and adaptation of the SESII-W, a Confirmatory Factor Analysis (CFA) was performed. Results: CFA resulted in a version consisting of 33 items divided into eight sub-factors, which were grouped into two higher-order factors (Sexual Excitation and Sexual Inhibition). The sub-factors demonstrated adequate internal consistency values except for Sexual Power Dynamics and Concerns about Sexual Function. Test-retest reliabilities were good. Their scores correlated with erotophilia, sexual sensation seeking, age at first intercourse, and number of sexual partners in the expected direction. Conclusions: The Spanish version of SESII-W has adequate psychometric guarantees for use in clinical practice and research, although it would be necessary to further revise factors that showed a lower level of reliability.  相似文献   
176.
ABSTRACT

This article looks at four different scholarly perspectives on ‘sacred’ – the ineffable sacred, the experienced sacred, the polarized sacred and the contextualized sacred – in order to draw out their implicit presuppositions about meaning. The first two stances presuppose that meaning depends on what bits of language are about (referentialism), and the other two stances presuppose that meaning depends on relations between bits of language (holism). The article concludes three things: these prominent views of ‘sacred’ rest on usually implicit or unrecognized assumptions about the nature of meaning; some of those assumptions explain why certain theories are contentious and problematic and others ground more promising and productive approaches.  相似文献   
177.
Background/Objective: Depression and suicide ideation regularly occur together. Yet, little is known about factors that buffer individuals against the development of suicide ideation. The present study investigated, whether positive mental health buffers the association between depression and suicide ideation in a longitudinal study design. Methods: A total of 207 German students (70.3% female; age: M = 26.04, SD = 5.33) were assessed at a baseline evaluation and again twelve months later. Data were collected using self-report questionnaires. Linear hierarchical regression analysis was used to analyze the data. Positive mental health was considered to moderate the impact of depression on suicide ideation – controlling for age and gender. Results: Positive mental health was shown to moderate the impact of depression on suicide ideation: in those students who reported higher levels of positive mental health, depression severity showed no association with suicide ideation over time. Conclusion: Positive mental health seems to confer resilience and should be taken into account, when assessing individuals for suicide risk.  相似文献   
178.
This study adds to the understanding of the relationship between qualitative job insecurity and employee in-role performance, by analysing the association longitudinally. While social exchange theory predicts that the relationship should be negative and bidirectional, the job preservation motivation model indicates a self-correcting mechanism, where job insecurity leads to increased performance, which, in turn, could decrease job insecurity. We developed competing hypotheses and examined them using structural equation modelling in a heterogeneous sample of 337 employees. For employees with a higher professional level, results pointed towards a reciprocal causal relationship between qualitative job insecurity and in-role performance, indicating a loss cycle. For employees with a lower professional level, results showed a small positive direct causal relationship between qualitative job insecurity and in-role performance, while the negative direct path from in-role performance to qualitative job insecurity did not reach statistical significance. This is the first study to test the diverging theoretical predictions of social exchange theory and the job preservation motivation model, with regard to the relationship between qualitative job insecurity and in-role performance. Being longitudinal, our study only allows us to hint at possible causal relationships between the involved variables, the chronological order being necessary, but not sufficient to prove causality.  相似文献   
179.
本研究考查了语言范畴是否会引起偏侧化颜色范畴知觉,并探讨了偏侧化颜色范畴知觉是语言范畴即时分类颜色还是长期与颜色联结的结果。实验中,以测量差别阈限的方法选定的渐变、相邻颜色知觉距离相当的A、B、C、D四种颜色(A、B为绿色,C、D为蓝色)为材料,以色词与颜色重组模式训练被试用4个人造词汇分别命名4种颜色,并让被试在训练前、第一次训练和第八次训练后均完成视觉搜索任务测试。经训练,原范畴内颜色(AB,CD)变成了范畴间颜色,原范畴间颜色(BC)仍为范畴间颜色。结果显示:被试在一次训练后能以新名字区分4种颜色,八次训练后掌握了4种颜色的新名字;在训练前测试中,出现了与蓝绿色相应的偏侧化颜色范畴知觉;在第八次训练后测试中,出现了与习得的语言范畴相应的偏侧化颜色范畴知觉,但在第一次训练后测试中并未出现这一效应。这些结果表明,语言范畴能引起偏侧化颜色范畴知觉,偏侧化颜色范畴知觉是语言范畴长期与颜色联结,而非即时分类颜色的结果。  相似文献   
180.
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