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881.
Distributions of students of four ethnic groups were statistically significantly different. 106 African-American students reported the lowest incidence of self-reported bruxism (9.4%), 452 Asian students the highest incidence (24.6%); 312 Euro-American and 225 Hispanic students' incidence was intermediate.  相似文献   
882.
883.
The fan effect: a tale of two theories.   总被引:8,自引:0,他引:8  
This article addresses J. R. Anderson and L. M. Reder's (1999) account of the differential fan effect reported by G. A. Radvansky, D. H. Spieler, and R. T. Zacks (1993). The differential fan effect is the finding of greater interference with an increased number of associations under some conditions, but not others, in a within-subjects mixed-list recognition test. Anderson and Reder concluded that the differential fan effects can be adequately explained by assuming differences in the weights given to concepts in long-term memory. When a broader range of data is considered, this account is less well supported. Instead, it is better to assume that the organization of information into referential representations, such as situation models, has a meaningful influence on long-term memory retrieval.  相似文献   
884.
Adults and 9-month-old infants were required to detect mistuned tones in multitone sequences. When 7-tone versions of a common nursery tune were generated from the Western major scale (unequal scale steps) or from an alternative scale (equal steps), infants detected the mistuned tones more accurately in the unequal-step context than in the equal-step context (Experiment 1). Infants and adults were subsequently tested with 1 of 3 ascending-descending scales (15 tones): (a) a potentially familiar scale (major) with unequal steps, (b) an unfamiliar scale with unequal steps, and (c) an unfamiliar scale with equal steps. Infants detected mistuned tones only in the scales with unequal steps (Experiment 2). Adults performed better on the familiar (major) unequal-step scale and equally poorly on both unfamiliar scales (Experiments 3 and 4). These findings are indicative of an inherent processing bias favoring unequal-step scales.  相似文献   
885.
This study explored whether self-efficacy and time perspective of homeless adults (N= 82) living in a shelter affected their coping strategies related to obtaining housing and employment. Participants with high self-efficacy searched more for housing and employment and stayed at the shelter for a shorter duration, whereas participants with low self-efficacy were more likely to request an extension of their stay at the shelter. Those high on future orientation had shorter durations of homelessness and were more likely to enroll in school and to report gaining positive benefits from their predicament, whereas those with a high present orientation had more avoidant coping strategies. Despite the predictive power of self-efficacy and future orientation of proactive search behaviors, there were no predictors of obtaining stable housing, which is a scarce resource in the area. However, a high present orientation predicted obtaining temporary housing. A present temporal perspective may be adaptive in finding short-term solutions to an unstable situation, such as homelessness. The role of time perspective in crisis situations is discussed, as well as the severe environmental constraints on the exercise of personal control over reality dictated by social, economic, and political forces.  相似文献   
886.
In 3 experiments, the authors examined movement space-time variability as a function of the force-time properties of the initial impulse in a movement timing task. In the range of motion and movement time task conditions, peak force, initial rate of force, and force duration were manipulated either independently or in combination across a range of parameter values. The findings showed that (a) impulse variability is predicted well by the elaboration of the isometric force variability scaling functions of L. G. Carlton, K. H. Kim, Y. T. Liu, and K. M. Newell (1993) to movement, and (b) the movement spatial and temporal outcome variability are complementary and well predicted by an equation treating the variance of force and time in Newton's 2nd law as independent random variables. Collectively, the findings suggest that movement outcome variability is the product of a coherent space-time function that is driven by the nonlinear scaling of the force-time properties of the initial impulse.  相似文献   
887.
888.
This study examined the effects of a programmes of experiential training in structured group counselling, based on the approach of Sheldon Rose. Participants were 32 undergraduate and graduate students, divided into three groups, who participated in the group work as part of a course in Core Counseling skills. The groups met for two hours per week for eight weeks. At the end of each exercise the participants completed a 12-item questionnaire giving their evalution and experience of the exercise they had just finished. The questionnaires were initially factors analysed and produced three main factg43ors, labelled task orientation, cohesion and conflict. Factor scores were used for all subsequent analyses. A series of one-way analyses of variance showed how the groups reacted to the different exercises, and discriminant analysis was used to determine how the climate and method of the individual groups could be differentially characterised in terms of the questionnaire factors. It was concluded that the membership of structured groups may be a major determinant of the group climate and experience.  相似文献   
889.
890.
In this paper I examine Quine's indispensability argument, with particular emphasis on what is meant by 'indispensable'. I show that confirmation theory plays a crucial role in answering this question and that once indispensability is understood in this light, Quine's argument is seen to be a serious stumbling block for any scientific realist wishing to maintain an anti-realist position with regard to mathematical entities.  相似文献   
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