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In the present study, we examined the impact of the interaction of environmental and task-induced attentional focus on time perception, specifically awareness of the time flow. We tested 48 participants in either a natural or urban setting over three 25- to 35-min sessions. We manipulated the within-subjects factor task by means of two tasks—one requiring directed attention on the task itself, the other undirected attention on the environment—alongside a control condition with no specific task. We measured time awareness, passage of time judgments, felt time judgments, and estimated time as dependent variables. For time awareness, we found an interaction between environment and task: in the natural environment, only a task requiring directed attention reduced time awareness; whereas, in the urban environment, both tasks reduced time awareness compared to the control condition. The results suggest that natural environments increase time awareness unless we focus our attention on a task.  相似文献   
133.
Animal Cognition - In the original publication of the article, the Fig. 4 was erroneously published.  相似文献   
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Two experiments examined effects of repetition and change on states of awareness in face recognition. Participants studied repeatedly presented photographs of faces, with the second presentation following either immediately after the first presentation (massed repetition) or following six intervening items (spaced repetition). To manipulate perceptual change, each repeated face was either identical or a mirror image of the first presentation. Subsequently, when recognising a face, participants indicated whether they consciously recollected its prior occurrence ("remembering") or recognised it on the basis of familiarity ("knowing"). Changes in appearance between repeated faces enhanced remember, but not know, responses, and these effects were accentuated for spaced, rather than massed, repetition. These findings suggest that distinctiveness of encoding supports the phenomenological experience of conscious remembering.  相似文献   
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Despite the historical trend in all Western societies to increase educational participation irrespective of students' social origin, the correlation between parents' education and socio-economic status and the educational outcomes of their offspring remains a rather universal phenomenon. Although comparative studies have consistently found this association in various nations which differ in many ways in their educational systems, little is known about the mechanism behind this effect. Drawing on the assumption that career decision points are the major gateway for social background influences, we assume that similarities, as well as differences in the structure of the correlation between parents' socioeconomic background and students' school success, can be explained. Using two longitudinal data sets from the United States (N=1425) and Germany (N=1755) covering the school careers from Grade 7 to Grade 10, the analyses supported the hypothesis that (a) achievement information is the best predictor of career relevant decisions in both nations, (b) parents' background variables are independent additional predictors of career decision but not for actual learning progress, and (c) the assumed accumulation process of social background influences is more pronounced in the German than in the U.S. school system.  相似文献   
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Data in social and behavioral sciences are often hierarchically organized though seldom normal, yet normal theory based inference procedures are routinely used for analyzing multilevel models. Based on this observation, simple adjustments to normal theory based results are proposed to minimize the consequences of violating normality assumptions. For characterizing the distribution of parameter estimates, sandwich-type covariance matrices are derived. Standard errors based on these covariance matrices remain consistent under distributional violations. Implications of various covariance estimators are also discussed. For evaluating the quality of a multilevel model, a rescaled statistic is given for both the hierarchical linear model and the hierarchical structural equation model. The rescaled statistic, improving the likelihood ratio statistic by estimating one extra parameter, approaches the same mean as its reference distribution. A simulation study with a 2-level factor model implies that the rescaled statistic is preferable.This research was supported by grants DA01070 and DA00017 from the National Institute on Drug Abuse and a University of North Texas faculty research grant. We would like to thank the Associate Editor and two reviewers for suggestions that helped to improve the paper.  相似文献   
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Concise formulas for the standard errors of component loading estimates   总被引:1,自引:0,他引:1  
Concise formulas for the asymptotic standard errors of component loading estimates were derived. The formulas cover the cases of principal component analysis for unstandardized and standardized variables with orthogonal and oblique rotations. The formulas can be used under any distributions for observed variables as long as the asymptotic covariance matrix for sample covariances/correlations is available. The estimated standard errors in numerical examples were shown to be equivalent to those by the methods using information matrices.The author is indebted to anonymous reviewers for the corrections and suggestions on this study, which have led to improvements of earlier versions of this article.  相似文献   
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