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981.
The goal of this study is to validate a Spanish version of the Physical Activity Enjoyment Scale (PACES, Kendzierski & DeCarlo, 1991), in the population of Spanish adolescent girls, and also to obtain a reduced version of the scale. For this purpose, reliability analysis was conducted, and construct validity was assessed in two steps: exploratory factor analysis and structural equation model with confirmatory factor analysis. The scale was administered to a sample of 2777 adolescent girls of Secondary Education, ages between 12-18 years. The results show the reliability of the instrument and the construct validity with a good fit of the model. The adapted scale was reduced to six items, a shorter and efficient scale that allows us to measure the enjoyment of physical activity.  相似文献   
982.
This work explores the significance of different types and sources of social support in the short- and middle-term prediction of volunteer permanence. Volunteers ( N = 1362) belonging to 109 different Spanish organizations were surveyed to gather social support data and other information related to factors traditionally associated with sustained volunteerism prediction. In spite of the fact that a relationship between social support and permanence was found, logistic regression analysis showed that social support variables did not appear to be relevant to make this kind of prediction at short term, because the only factors associated with volunteers' permanence in the multivariate model obtained were the volunteers' previous time in the organization, their intention of remaining in service, and their sex and religious attitudes. In contrast, at middle term, social support and, in particular, informational social support from other volunteers was significant, integrating the multivariate model with the other aforementioned factors, except for sex.  相似文献   
983.
This article examines the role of subjective familiarity in the implicit and explicit learning of artificial grammars. Experiment 1 found that objective measures of similarity (including fragment frequency and repetition structure) predicted ratings of familiarity, that familiarity ratings predicted grammaticality judgments, and that the extremity of familiarity ratings predicted confidence. Familiarity was further shown to predict judgments in the absence of confidence, hence contributing to above-chance guessing. Experiment 2 found that confidence developed as participants refined their knowledge of the distribution of familiarity and that differences in familiarity could be exploited prior to confidence developing. Experiment 3 found that familiarity was consciously exploited to make grammaticality judgments including those made without confidence and that familiarity could in some instances influence participants' grammaticality judgments apparently without their awareness. All 3 experiments found that knowledge distinct from familiarity was derived only under deliberate learning conditions. The results provide decisive evidence that familiarity is the essential source of knowledge in artificial grammar learning while also supporting a dual-process model of implicit and explicit learning.  相似文献   
984.
Affirmative action is a problematic, but common, organizational approach to redressing gender discrimination as it fails to address discourses underlying organizational definitions and practices in highly masculinized sites like English football. Unstructured interviews with 27 key personnel and participants in coach education in the north of England within a regional “division” of the organization regulating English football (“The FA”) were conducted to explore the gendered construction and enactment of football and coaching, and the framing of women-only (separatist) coaching courses. Critical discourse analysis identified the deployment of discourses concerning the undermining of standards and the privileging of women as strategies used to neutralize the significance of gender and previous gender discrimination, while re/producing the centrality of masculinity for key definitions and identities. This paper is based on Beth Fielding-Lloyd’s Ph.D. dissertation undertaken at the Centre for Human Communication, Manchester Metropolitan University, UK under the supervision of Dr. Lindsey Mean. Authors are listed alphabetically.  相似文献   
985.
Evidence indicates that brain endocannabinoids are involved in memory processing. However, the participation of CB1 and CB2 cannabinoid receptors in recognition memory has not been yet conclusively determined. Therefore, we evaluated the effect of the posttraining activation of hippocampal cannabinoid receptors on the consolidation of object recognition memory. Rats with infusion cannulae stereotaxically aimed to the CA1 region of the dorsal hippocampus were trained in an object recognition learning task involving exposure to two different stimulus objects. Memory retention was assessed at different times after training. In the test sessions, one of the objects presented during training was replaced by a novel one. When infused in the CA1 region immediately after training, the non-selective cannabinoid receptor agonist WIN-55,212-2 and the endocannabinoid membrane transporter inhibitor VDM-11 blocked long-term memory retention in a dose-dependent manner without affecting short-term memory, exploratory behavior, anxiety state or the functionality of the hippocampus. The amnesic effect of WIN-55,212-2 and VDM-11 was not due to state-dependency and was completely reversed by co-infusion of the CB1 receptor antagonist AM-251 and mimicked by the CB1 receptor agonist ACEA but not by the CB2 receptor agonists JWH-015 and palmitoylethanolamide. Our data indicate that activation of hippocampal CB1 receptors early after training hampers consolidation of object recognition memory.  相似文献   
986.
Cluster randomized trials (CRTs) have been widely used in field experiments treating a cluster of individuals as the unit of randomization. This study focused particularly on situations where CRTs are accompanied by a common complication, namely, treatment noncompliance or, more generally, intervention nonadherence. In CRTs, compliance may be related not only to individual characteristics but also to the environment of clusters individuals belong to. Therefore, analyses ignoring the connection between compliance and clustering may not provide valid results. Although randomized field experiments often suffer from both noncompliance and clustering of the data, these features have been studied as separate rather than concurrent problems. On the basis of Monte Carlo simulations, this study demonstrated how clustering and noncompliance may affect statistical inferences and how these two complications can be accounted for simultaneously. In particular, the effect of the intervention on individuals who not only were assigned to active intervention but also abided by this intervention assignment (complier average causal effect) was the focus. For estimation of intervention effects considering noncompliance and data clustering, an ML-EM estimation method was employed.  相似文献   
987.
In multilevel modeling (MLM), group-level (L2) characteristics are often measured by aggregating individual-level (L1) characteristics within each group so as to assess contextual effects (e.g., group-average effects of socioeconomic status, achievement, climate). Most previous applications have used a multilevel manifest covariate (MMC) approach, in which the observed (manifest) group mean is assumed to be perfectly reliable. This article demonstrates mathematically and with simulation results that this MMC approach can result in substantially biased estimates of contextual effects and can substantially underestimate the associated standard errors, depending on the number of L1 individuals per group, the number of groups, the intraclass correlation, the sampling ratio (the percentage of cases within each group sampled), and the nature of the data. To address this pervasive problem, the authors introduce a new multilevel latent covariate (MLC) approach that corrects for unreliability at L2 and results in unbiased estimates of L2 constructs under appropriate conditions. However, under some circumstances when the sampling ratio approaches 100%, the MMC approach provides more accurate estimates. Based on 3 simulations and 2 real-data applications, the authors evaluate the MMC and MLC approaches and suggest when researchers should most appropriately use one, the other, or a combination of both approaches.  相似文献   
988.
One hundred and thirty-one adults belonging to four age groups (19-26, 50-59, 60-69 and 70-82 years) performed a spatial stimulus-response consistency task in which the response dimension (left or right) overlapped relevant and irrelevant stimulus dimensions. The influence of the irrelevant stimulus dimension on response time was significantly greater in the middle age groups than among 19-26 year-olds, and significantly greater in the highest age group than in any other. This pattern persisted when allowance was made for a significant age-related increase in processing time (measured as reaction time in a single-stimulus, single-response task). It is concluded that in tasks of the kind used, the elderly resist interference from the irrelevant information less easily than do younger persons. Interestingly, comparison of Vincentized quintiles suggested that the effect of the irrelevant stimulus dimension decreased with increasing response time among 19-26 year-olds, but increased with response time among 70-82 year-olds.  相似文献   
989.
The most commonly employed item selection rule in a computerized adaptive test (CAT) is that of selecting the item with the maximum Fisher information for the estimated trait level. This means a highly unbalanced distribution of item‐exposure rates, a high overlap rate among examinees and, for item bank management, strong pressure to replace items with a high discrimination parameter in the bank. An alternative for mitigating these problems involves, at the beginning of the test, basing item selection mainly on randomness. As the test progresses, the weight of information in the selection increases. In the present work we study, for two selection rules, the progressive methods ( Revuelta & Ponsoda, 1998 ) and the proportional method ( Segall, 2004a ), different functions that define the weight of the random component according to the position in the test of the item to be administered. The functions were tested in simulated item banks and in an operative bank. We found that both the progressive and the proportional methods tolerate a high weight of the random component with minimal or zero loss of accuracy, while bank security and maintenance are improved.  相似文献   
990.
Previous research by Dupoux et al. [Dupoux, E., Pallier, C., Sebastián, N., & Mehler, J. (1997). A destressing "deafness" in French? Journal of Memory Language 36, 406-421; Dupoux, E., Peperkamp, S., & Sebastián-Gallés (2001). A robust method to study stress' deafness. Journal of the Acoustical Society of America 110, 1608-1618.] found that French speakers, as opposed to Spanish ones, are impaired in discrimination tasks with stimuli that vary only in the position of stress. However, what was called stress 'deafness' was only found in tasks that used high phonetic variability and memory load, not in cognitively less demanding tasks such as single token AX discrimination. This raised the possibility that instead of a perceptual problem, monolingual French speakers might simply lack a metalinguistic representation of contrastive stress, which would impair them in memory tasks. We examined a sample of 39 native speakers of French who underwent formal teaching of Spanish after age 10, and varied in degree of practice in this language. Using a sequence recall task, we observed in all our groups of late learners of Spanish the same impairment in short-term memory encoding of stress contrasts that was previously found in French monolinguals. Furthermore, using a speeded lexical decision task with word-nonword minimal pairs that differ only in the position of stress, we found that all late learners had much difficulty in the use of stress to access the lexicon. Our results show that stress 'deafness' is better interpreted as a lasting processing problem resulting from the impossibility for French speakers to encode contrastive stress in their phonological representations. This affects their memory encoding as well as their lexical access in on-line tasks. The generality of such a persistent suprasegmental 'deafness' is discussed in relation to current findings and models on the perception of non-native phonological contrasts.  相似文献   
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