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951.
This paper provides a review of career development research studies publishedin Australia and New Zealand between 1995 and2000. The review has grouped the literatureaccording to the categories of careerdevelopment theory, career developmentconstructs, career-related decision-making,gender, cultural comparisons, career programsfor children and training programs for adults.These groupings were created to correspond withthe main focus of each study.  相似文献   
952.
953.
Evolutionary theory predicts that most populations should consist of roughly as many males as females. Recently, a variety of populations have been described which show very different proportions of the two sexes, especially in invertebrate species that contain individuals whose offspring are almost all female. Some of these instances can now be explained by the diverse actions of various ‘selfish’ elements residing in the cytoplasm of the individuals, which are transmitted exclusively through the female line. These instances of curious sex ratios exemplify an important principle: the fitness of genes, rather than of individuals, is the primary currency of evolution.  相似文献   
954.
Twenty acquisition curves were obtained from each of 8 pigeons in a free-operant choice procedure. Every condition began with a phase in which two response keys had equal probabilities of reinforcement, and, as a result, subjects’ responses were divided fairly evenly between the two keys. This was followed by a phase in which one key had a higher probability of reinforcement than the other, and the development of preference was observed. In all but a few cases, response proportions increased for the key with the higher probability of reinforcement. In most conditions, the two probabilities differed by .06, but the actual probabilities varied (from .16 and .10 in one condition to .07 and .01 in another). Development of preference for the key with the higher probability of reinforcement was slower when the ratio of the two reinforcement probabilities was small (.16/.10) than when it was large (.07/.01). This finding is inconsistent with the predictions of several different quantitative models of acquisition, including the kinetic model (Myerson & Miezin, 1980) and the ratio-invariance model (Horner & Staddon, 1987). However, the finding is consistent with a hypothesis based on Weber’s law, which states that the two alternatives are more discriminable when the ratio of their reinforcement probabilities is larger, and, as a result, the acquisition of preference is faster.  相似文献   
955.
Computer and video games are a prevalent form of entertainment in which the purpose of the design is to engage players. Game designers incorporate a number of strategies and tactics for engaging players in “gameplay.” These strategies and tactics may provide instructional designers with new methods for engaging learners. This investigation presents a review of game design strategies and the implications of appropriating these strategies for instructional design. Specifically, this study presents an overview of the trajectory of player positioning or point of view, the role of narrative, and methods of interactive design. A comparison of engagement strategies in popular games and characteristics of engaged learning is also presented to examine how strategies of game design might be integrated into the existing framework of engaged learning. The preparation of this article was supported in part by the Proctor & Gamble Interactive Media Fellows grant. The ideas expressed in this paper do not necessarily reflect the position of the grant agency. R Thanks to the ETR&D Development Editor, J. Michael Spector, and the reviewers for their insightful comments and suggestions. Thanks, too, to John C. Belland and Keith A. Hall for their advice and mentoring.  相似文献   
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957.
This study investigated patterns of college attendance using data from a nationwide and contemporary sample of 2112 rural youth. We found that more than half of rural youth attended two-year institutions at some point during their college career and about a fourth initially enrolled in a two-year college before enrolling in a four-year college. Results also revealed that parental education, college preparatory track and preparation experiences, and teacher expectations predicted students’ college attendance patterns. Our findings point to the importance of two-year colleges and highlight the influence of family characteristics and students’ schooling experiences in the postsecondary trajectories of rural youth.  相似文献   
958.
The relation of parenting style to adolescent school performance   总被引:21,自引:0,他引:21  
This article develops and tests a reformation of Baumrind's typology of authoritarian, permissive, and authoritative parenting styles in the context of adolescent school performance. Using a large and diverse sample of San Francisco Bay Area high school students (N = 7,836), we found that both authoritarian and permissive parenting styles were negatively associated with grades, and authoritative parenting was positively associated with grades. Parenting styles generally showed the expected relation to grades across gender, age, parental education, ethnic, and family structure categories. Authoritarian parenting tended to have a stronger association with grades than did the other 2 parenting styles, except among Hispanic males. The full typology best predicted grades among white students. Pure authoritative families (high on authoritative but not high on the other 2 indices) had the highest mean grades, while inconsistent families that combine authoritarian parenting with other parenting styles had the lowest grades.  相似文献   
959.
In this work, support vector classification (SVC) algorithm was used to build structure-activity relationship (SAR) model of the 5-hydroxytryptamine type 3 (5-HT3 ) receptor antagonists with 26 compounds. In a benchmark test, SVC was compared with several techniques of machine learning currently used in the field. The prediction performance of the model was discussed on the basis of the leave-one-out cross-validation. The results show that the accuracy of prediction of SVC model was higher than those of back propagation artificial neural network (BP ANN), K-nearest neighbor (KNN) and Fisher methods.  相似文献   
960.
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