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141.
This study aimed to analyze the psychometric properties of a new scale: the Out-group Threat Perception Scale (OTPS). The OTPS was designed to measure the perception of out-group threat, an important psychosocial variable that is closely related to negative attitudes towards out-groups. Three hundred and two Spanish participants responded to the OTPS in reference to the following out-groups: Moroccans (N= 102), Romanians (N= 101) and Ecuadorian immigrants (N= 99). The reliability and item analyses showed that the scale had good internal consistency. Factor analyses yielded two independent dimensions: Realistic Threat and Symbolic Threat. Correlational analyses showed that the OTPS correlated significantly with several psychosocial variables. The present findings suggest that the OTPS is a reliable and valid measure, and it can be a useful instrument to study intergroup relationships in our country.  相似文献   
142.
The objective of this study was to validate in a sample of 205 coronary patients a factor model for the BDI-II, especially a model that would allow for modeling of depressive symptoms after explicitly removing bias related to somatic symptoms of depression that would overlap those of heart disease. Exploratory and confirmatory factor analyses for ordinal data were conducted. A one-factor model, six correlated two-factor models and, derivatives thereof, seven models with a single General Depression factor and two uncorrelated factors, were analyzed. Exploratory analysis extracted two factors, Somatic-affective and Cognitive. Confirmatory factor analyses showed the worst fit for the one-factor model. Two-factor models were surpassed in goodness of fit by the models of general-factor and group factors. Among these, the General, Somatic-affective and Cognitive (G-Sa-C) model of Beck with students is noteworthy. The reduced General, Somatic and Cognitive (G-S-C) model of Ward showed the worst goodness of fit. Our model surpasses the cutoff criteria of all fit indexes. We conclude that the inclusion of a general-factor and group factors in all the models surpasses the results of G-S-C model and, therefore, questions it. The G-Sa-C model is strengthened.  相似文献   
143.
The reliability generalization (RG) approach is a kind of meta-analysis that aims to statistically integrate a set of independent reliability coefficients obtained in several applications of a test, with the purpose of characterizing the measurement error and determining which factors related to the studies and samples can explain its variability. Diverse procedures have been proposed in the literature for averaging a set of independent alpha coefficients, and there is no consensus about which methods are best. Here, we present the results of a Monte Carlo simulation study, comparing the performance of twelve procedures proposed in Feldt and Charter, in terms of bias and mean square error. These procedures differ from each other in the transformation (or not) of the coefficients, and in the application or not of a weighting scheme based on sample size. Our results recommend using weighted methods in contrast to unweighted ones, and transforming the coefficients by the Hakstian and Whalen's proposal or by the proposal based on the square root of the inverse alpha coefficient. Lastly, we discuss the relations between the diverse procedures for averaging alpha coefficients with fixed-effects, random-effects, and varying coefficients models.  相似文献   
144.
People perform leisure activities (LA) every day; pursuits that entail applying cognitive, physical and social abilities. As in old age, doing LA during early and middle adulthood is related to a reduced risk of dementias, probably by generating a cognitive reserve. As it is possible that a relation between doing LA and working memory (WM) efficiency exists in young adults, we assessed whether the diversity and frequency of LA are related to WM efficiency in this population. Ninety-three healthy young subjects solved the n-back task at two levels of difficulty (2, 3), and answered an LA questionnaire on the activities in which they had participated in the month prior to the experiment. Subjects were classified separately on their scores for (1) diversity (high/low) and (2) frequency (high/low) in order to test the relation between each variable and WM efficiency. Though no differences were found, a subsequent analysis of the average of diversity and frequency ratios of LA performance taken together-the diversity/frequency index-showed that low diversity plus low frequency was significantly associated with reduced WM efficiency at this age; results that suggest that frequent participation in diverse LA during youth is related to WM efficiency.  相似文献   
145.
J Gervain  R Guevara Erra 《Cognition》2012,125(2):263-287
Does statistical learning (Saffran, Aslin, &; Newport, 1996) offer a universal segmentation strategy for young language learners? Previous studies on large corpora of English and structurally similar languages have shown that statistical segmentation can be an effective strategy. However, many of the world’s languages have richer morphological systems, with sometimes several affixes attached to a stem (e.g. Hungarian: iskoláinkban: iskolá-i-nk-ban school.pl.poss1pl.inessive ‘in our schools’). In these languages, word boundaries and morpheme boundaries do not coincide. Does the internal structure of words affect segmentation? What word forms does segmentation yield in morphologically rich languages: complex word forms or separate stems and affixes? The present paper answers these questions by exploring different segmentation algorithms in infant-directed speech corpora from two typologically and structurally different languages, Hungarian and Italian. The results suggest that the morphological and syntactic type of a language has an impact on statistical segmentation, with different strategies working best in different languages. Specifically, the direction of segmentation seems to be sensitive to the affixation order of a language. Thus, backward probabilities are more effective in Hungarian, a heavily suffixing language, whereas forward probabilities are more informative in Italian, which has fewer suffixes and a large number of phrase-initial function words. The consequences of these findings for potential segmentation and word learning strategies are discussed.  相似文献   
146.
Time, an everyday yet fundamentally abstract domain, is conceptualized in terms of space throughout the world's cultures. Linguists and psychologists have presented evidence of a widespread pattern in which deictic time-past, present, and future-is construed along the front/back axis, a construal that is linear and ego-based. To investigate the universality of this pattern, we studied the construal of deictic time among the Yupno, an indigenous group from the mountains of Papua New Guinea, whose language makes extensive use of allocentric topographic (uphill/downhill) terms for describing spatial relations. We measured the pointing direction of Yupno speakers' gestures-produced naturally and without prompting-as they explained common expressions related to the past, present, and future. Results show that the Yupno spontaneously construe deictic time spatially in terms of allocentric topography: the past is construed as downhill, the present as co-located with the speaker, and the future as uphill. Moreover, the Yupno construal is not linear, but exhibits a particular geometry that appears to reflect the local terrain. The findings shed light on how, our universal human embodiment notwithstanding, linguistic, cultural, and environmental pressures come to shape abstract concepts.  相似文献   
147.
While perceiving speech, people see mouth shapes that are systematically associated with sounds. In particular, a vertically stretched mouth produces a /woo/ sound, whereas a horizontally stretched mouth produces a /wee/ sound. We demonstrate that hearing these speech sounds alters how we see aspect ratio, a basic visual feature that contributes to perception of 3D space, objects and faces. Hearing a /woo/ sound increases the apparent vertical elongation of a shape, whereas hearing a /wee/ sound increases the apparent horizontal elongation. We further demonstrate that these sounds influence aspect ratio coding. Viewing and adapting to a tall (or flat) shape makes a subsequently presented symmetric shape appear flat (or tall). These aspect ratio aftereffects are enhanced when associated speech sounds are presented during the adaptation period, suggesting that the sounds influence visual population coding of aspect ratio. Taken together, these results extend previous demonstrations that visual information constrains auditory perception by showing the converse - speech sounds influence visual perception of a basic geometric feature.  相似文献   
148.
In baseball batting, golf putting, and dart throwing, successful players estimate the size of the target object to be bigger than their less successful counterparts. While more and more empirical evidence is accumulated supporting the existence of this intriguing phenomenon, an explanation of the processes underpinning this effect remains to be provided. Here, we re-analysed data from a dart throwing experiment to examine the proposal--recently put forward by Proffitt and Linkenauger (in press)--that the variability in target-related performance may serve as a scaling metric for perceived target size which may explain why actors who perform consistently close to the target perceive the target to be bigger. Our results confirm that less variability in target-related performance in darts relates to perceiving the target as being bigger, thereby providing initial support for Proffitt and Linkenauger's proposal.  相似文献   
149.
Presently, little is known about the effect of curved backgrounds against which the target stimulus is presented on precision in stereoacuity. The experiment analyzed the influence of stimulus orientation and 3D background configuration on stereoscopic vision. Participants were instructed to perform 3D visual alignment tasks on a modified version of the Howard-Dolman apparatus, whereupon precision in depth perception for different curved backgrounds (flat, black, concave, and convex) was evaluated. In addition, the influence of stimulus orientation (0 degrees, 45 degrees, and 90 degrees) on precision was examined. The findings revealed an underestimation in the perceived depth in all background configurations, indicating highest and lowest precision outcomes for convex and concave backgrounds, respectively. In addition, a significant interaction of background and orientation was found. It was concluded that, in a real environment, background local depth cues are integrated with target stimuli to contribute to depth perception.  相似文献   
150.
Alcohol use and its associated problems among university students have attracted empirical investigation by researchers and scholars. While many of these studies have reported a very high level of alcohol consumption and highlighted the various problems this portends, alcohol-related perceptions of this vulnerable population, which could be germane to intervention aimed at curtailing the problem, have remained largely under-researched. This cross-sectional survey examined the use and perceptions of alcohol by student-patrons (n = 1,705) of beer parlours or ‘joints’ in three university communities in Southwest Nigeria. Respondents were interviewed using AUDIT, a socio-demographic prototype and an open-ended section on alcohol-related perceptions of the students. Findings indicated that overall, 72% of the respondents perceived that alcohol is good for socializing, 68% perceived that alcohol is good in the aspect of stress reduction, 58% believed that alcohol consumption is indicative of maturity, 36% perceived that alcohol enhances their sexual performance while 39% perceived that alcohol serves to enhance alertness/concentration. Results also showed that gender (β = −. 23; p < .05), paternal alcohol use (β = .36; p < .01), parental socio-economic status (β = .33; p < .01), and residential status of university of respondents (β = .21; p < .05) significantly predicted alcohol use. The study concluded that perceptions about alcohol are very germane to understanding students’ alcohol use and should be reckoned with in designing intervention programmes. The need to adopt a ‘client-centered’ approach to the problem of student drinking behaviour was emphasized.  相似文献   
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