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Children are sensitive to a number of considerations influencing distributions of resources, including equality, equity, and reciprocity. We tested whether children use a specific type of reciprocity norm—market norms—in which resources are distributed differentially based strictly on amount offered in return. In two studies, 195 children 5–10 years and 60 adults distributed stickers to friends offering same or different amounts of money. Overall, participants distributed more equally when offers were the same and more unequally when offers were different. Although sensitive to why friends offered different amounts of money, children increasingly incorporated market norms into their distributions with age, as the oldest children and adults distributed more to those offering more, irrespective of the reasons provided. 相似文献
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As a group, students with learning disabilities (LD) have social difficulties. One possible explanation for these difficulties is the unique way they process social information. Although students with LD may differ from their nondisabled peers in their social cognition, investigators have suggested the presence of subgroups within the population of students with LD who may differ in their social competence and, thereby, shed light on the source of the difficulties. The present exploratory study examined how two subgroups of students with LD in inclusive settings, students with high and low social status, perceive social situations. Using a sociometric technique, three students with LD receiving high social‐status ratings and three students with LD receiving low social‐status ratings were identified. A qualitative approach was used to gather and evaluate data from the participants and their teachers. Results suggested differences between the two subgroups in their (1) sensitivity to cues in the environment, (2) interpretation of social situations in relation to their own experiences, and (3) levels of self‐control. Implications of these findings for practice and future research are discussed. 相似文献
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Measuring Search Engine Quality 总被引：12，自引：3，他引：9
The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures. 相似文献
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本期推出两篇短小精美的文章,表达了父爱的温馨,有兴趣的读者朋友不妨将它们作为范文来诵渎。 相似文献
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