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211.
Several methods are available to estimate the total and residual amount of heterogeneity in meta‐analysis, leading to different alternatives when estimating the predictive power in mixed‐effects meta‐regression models using the formula proposed by Raudenbush (1994, 2009). In this paper, a simulation study was conducted to compare the performance of seven estimators of these parameters under various realistic scenarios in psychology and related fields. Our results suggest that the number of studies (k) exerts the most important influence on the accuracy of the results, and that precise estimates of the heterogeneity variances and the model predictive power can only be expected with at least 20 and 40 studies, respectively. Increases in the average within‐study sample size () also improved the results for all estimators. Some differences among the accuracy of the estimators were observed, especially under adverse (small k and ) conditions, while the results for the different methods tended to convergence for more optimal scenarios.  相似文献   
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Here, two studies seek to characterize a parsimonious common‐denominator personality structure with optimal cross‐cultural replicability. Personality differences are observed in all human populations and cultures, but lexicons for personality attributes contain so many distinctions that parsimony is lacking. Models stipulating the most important attributes have been formulated by experts or by empirical studies drawing on experience in a very limited range of cultures. Factor analyses of personality lexicons of nine languages of diverse provenance (Chinese, Korean, Filipino, Turkish, Greek, Polish, Hungarian, Maasai, and Senoufo) were examined, and their common structure was compared to that of several prominent models in psychology. A parsimonious bivariate model showed evidence of substantial convergence and ubiquity across cultures. Analyses involving key markers of these dimensions in English indicate that they are broad dimensions involving the overlapping content of the interpersonal circumplex, models of communion and agency, and morality/warmth and competence. These “Big Two” dimensions—Social Self‐Regulation and Dynamism—provide a common‐denominator model involving the two most crucial axes of personality variation, ubiquitous across cultures. The Big Two might serve as an umbrella model serving to link diverse theoretical models and associated research literatures.  相似文献   
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School System Evaluation by Value Added Analysis Under Endogeneity   总被引:1,自引:0,他引:1  
Value added is a common tool in educational research on effectiveness. It is often modeled as a (prediction of a) random effect in a specific hierarchical linear model. This paper shows that this modeling strategy is not valid when endogeneity is present. Endogeneity stems, for instance, from a correlation between the random effect in the hierarchical model and some of its covariates. This paper shows that this phenomenon is far from exceptional and can even be a generic problem when the covariates contain the prior score attainments, a typical situation in value added modeling. Starting from a general, model-free definition of value added, the paper derives an explicit expression of the value added in an endogeneous hierarchical linear Gaussian model. Inference on value added is proposed using an instrumental variable approach. The impact of endogeneity on the value added and the estimated value added is calculated accurately. This is also illustrated on a large data set of individual scores of about 200,000 students in Chile.  相似文献   
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Families play an important role in the lives of individuals with mental illness. Coping with the strain of shifting roles and multiple challenges of caregiving can have a huge impact. Limited information exists regarding race-related differences in families’ caregiving experiences, their abilities to cope with the mental illness of a loved one, or their interactions with mental health service systems. This study examined race-related differences in the experiences of adults seeking to participate in the National Alliance on Mental Illness Family-to-Family Education Program due to mental illness of a loved one. Participants were 293 White and 107 African American family members who completed measures of problem- and emotion-focused coping, knowledge about mental illness, subjective illness burden, psychological distress, and family functioning. Multiple regression analyses were used to determine race-related differences. African American caregivers reported higher levels of negative caregiving experiences, less knowledge of mental illness, and higher levels of both problem-solving coping and emotion-focused coping, than White caregivers. Mental health programs serving African American families should consider targeting specific strategies to address caregiving challenges, support their use of existing coping mechanisms and support networks, and increase their knowledge of mental illness.  相似文献   
216.
In literates, reading is a fundamental channel for acquiring new vocabulary both in the mother tongue and in foreign languages. By using an artificial language learning task, we examined the acquisition of novel written words and their embedded regularities (an orthographic surface feature and a syllabic feature) in three groups of university students with different exposures (Group 1 saw 2 words once, Group 2 saw 20 words once, Group 3 saw 20 words three times). Recognition memory results for Groups 2 and 3 indicated that adults can learn novel written words even with just a single exposure, albeit repeated exposure improved target detection. A generalization task revealed that even the minimal exposure in Group 1 was enough for acquisition of the two embedded regularities. More exemplars and repeated exposure provided more robust effects for the syllable regularity. Finally, post-test interview showed that repeated exposure was needed to become aware of the regularities. The present results show that adults learn novel written words and their inherent regularities in a fast and effective fashion.  相似文献   
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We examine a distinctive kind of problem for decision theory, involving what we call discontinuity at infinity. Roughly, it arises when an infinite sequence of choices, each apparently sanctioned by plausible principles, converges to a ‘limit choice’ whose utility is much lower than the limit approached by the utilities of the choices in the sequence. We give examples of this phenomenon, focusing on Arntzenius et al.’s Satan’s apple, and give a general characterization of it. In these examples, repeated dominance reasoning (a paradigm of rationality) apparently gives rise to a situation closely analogous to having intransitive preferences (a paradigm of irrationality). Indeed, the agents in these examples are vulnerable to a money pump set-up despite having preferences that exhibit no obvious defect of rationality. We explore several putative solutions to such problems, particularly those that appeal to binding and to deliberative dynamics. We consider the prospects for these solutions, concluding that if they fail, the examples show that money pump arguments are invalid.  相似文献   
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