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31.
The transition from elementary to junior high school is difficult for some children, as indicated by a drop in grades in the new school setting from the beginning to end of the year. Finer-grain analysis of grade trajectories in the first year of junior high may reflect important differences among groups. In the present study, variables predicting linear and quadratic grade trajectories over the seventh grade were examined using a structural equation model (SEM, AMOS-4) and curve estimation procedures. Participants were 214 boys and 259 girls entering junior high (52% Anglo, 36% Hispanics, primarily of Mexican descent, and 12% Blacks). Three trajectory patterns were observed: “sliders,” students who showed a fairly steady grade decline over the year (characteristic of Anglos), “steadies,” students who varied little over the year (characteristic of Blacks), and “rebounders,” students whose grades dropped to a minimum in the fourth 6-week period, then showed limited recovery (characteristic of Hispanics). In the SEM, a lower intercept (representing the average of sixth grade grades) was associated with minority ethnic/racial status (Hispanic or Black), using more emotional discharge to cope, having a lower percentage of adults in the support network, poorer family functioning, and greater depression. Being Black was associated with a positive path coefficient to the linear slope of the grade trajectory, while a negative path coefficient was associated with using more emotional discharge in coping. The quadratic element (drop in grades with some recovery) was more pronounced for Hispanic participants, less pronounced for Black participants, and more pronounced when poorer family functioning was reported. Curve estimation procedures confirmed these ethnic/racial group differences. Reasons for such differences and their implications for schools and families are discussed. 相似文献
32.
Gow DW 《Brain and language》2012,121(3):273-288
Current accounts of spoken language assume the existence of a lexicon where wordforms are stored and interact during spoken language perception, understanding and production. Despite the theoretical importance of the wordform lexicon, the exact localization and function of the lexicon in the broader context of language use is not well understood. This review draws on evidence from aphasia, functional imaging, neuroanatomy, laboratory phonology and behavioral results to argue for the existence of parallel lexica that facilitate different processes in the dorsal and ventral speech pathways. The dorsal lexicon, localized in the inferior parietal region including the supramarginal gyrus, serves as an interface between phonetic and articulatory representations. The ventral lexicon, localized in the posterior superior temporal sulcus and middle temporal gyrus, serves as an interface between phonetic and semantic representations. In addition to their interface roles, the two lexica contribute to the robustness of speech processing. 相似文献
33.
The primary aim of this research was to investigate associations that depression severity and trait anxiety have with reactions to specific, identifiable thoughts experienced by persons with varying levels of personality disorder (PD) pathology as they went about their day-to-day lives. Ninety-eight psychotropic medication-free persons participated in an experience sampling assessment procedure over four consecutive days, during which participants recorded specific thoughts experienced moments before a page signal was received and corresponding ratings of thought discomfort. Thought discomfort, regarded as an emotional reaction to thoughts or their evaluation, was moderately associated with several forms of PD pathology, particularly Cluster C pathology. Once depression severity and trait anxiety were controlled, however, associations between PD pathology and thought discomfort were eliminated. Findings from this research generally support the mood-congruence of negatively valenced thoughts in relation to PD pathology. 相似文献
34.
Sigal Kaplan Carlo Giacomo Prato 《Transportation Research Part F: Traffic Psychology and Behaviour》2012,15(1):9-24
A considerable gap exists between the behavioral paradigm of choice set formation in route choice and its representation in route choice modeling. While travelers form their viable choice set by retaining routes that satisfy spatiotemporal constraints, existing route generation techniques do not account for individual-related spatiotemporal constraints. This paper reduces the gap by proposing a route choice model incorporating spatiotemporal constraints and latent traits. The proposed approach combines stochastic route generation with a latent variable semi-compensatory model representing constraint-based choice set formation followed by compensatory choice. The model is applied to data focusing on habitual commuting route choice behavior in morning peak hours. Results show (i) the possibility of inferring spatiotemporal constraints from considered routes, (ii) the importance of incorporating spatiotemporal constraints and latent traits in route choice models, and (iii) the linkage between spatiotemporal constraints and time saving, spatial and mnemonic abilities. 相似文献
35.
The present study illustrates the usefulness of finite mixture of generalized linear models (GLMs) to examine variability in cognitive strategies during childhood. More precisely, it addresses this variability in set-shifting situations where task-goal updating is endogenously driven. In a task-switching paradigm 5–6-year-olds had to switch between color- and shape-matching rules as a function of a predetermined, predictable task sequence. A finite mixture of GLMs was fitted to explore individual differences in performance. The statistical model revealed five response profiles, defined by accuracy and response times. These response profiles likely correspond to different cognitive strategies with varying efficiency and differential relations to working memory capacity (assessed by backward digit span). These results illustrate the heuristic value of statistical modeling to reveal the behavioral and cognitive variability in the temporal dynamics of children's cognitive functioning. 相似文献
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M. R. Yilmaz 《Journal of Multi-Criteria Decision Analysis》1992,1(2):65-80
Despite being in existence for many decades, normative decision theory has not become a commonly used tool for real-world decisions. This paper considers the reasons for this situation and suggestions for circumventing them. The main suggestion involves a two-stage framework in terms of the information available to the decision maker and his/her expectations under the available acts. This framework is well suited for decisions with incomplete structure, which is typical of real decision situations. Within this framework a specific multiplicative model is also discussed. 相似文献
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