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排序方式: 共有1371条查询结果,搜索用时 15 毫秒
81.
Many studies have examined associations between children's theory of mind and social behavior with familiar peers, but to date none have examined how theory of mind might relate to behavior toward unfamiliar peers in a play setting. Forty-four 4-year-olds (21 girls, 23 boys) participated in standard theory-of-mind tasks and in a play session with 3 or 4 other children who were unfamiliar. Children were also tested on general vocabulary ability. No relations were found between theory of mind and social engagement. However, positive associations were found between theory of mind and time spent observing, but not interacting with, other children. Possible explanations of the links between theory of mind, temperament, and social interest are considered.  相似文献   
82.
83.
The critical task of predicting clicks on search advertisements is typically addressed by learning from historical click data. When enough history is observed for a given query-ad pair, future clicks can be accurately modeled. However, based on the empirical distribution of queries, sufficient historical information is unavailable for many query-ad pairs. The sparsity of data for new and rare queries makes it difficult to accurately estimate clicks for a significant portion of typical search engine traffic. In this paper we provide analysis to motivate modeling approaches that can reduce the sparsity of the large space of user search queries. We then propose methods to improve click and relevance models for sponsored search by mining click behavior for partial user queries. We aggregate click history for individual query words, as well as for phrases extracted with a CRF model. The new models show significant improvement in clicks and revenue compared to state-of-the-art baselines trained on several months of query logs. Results are reported on live traffic of a commercial search engine, in addition to results from offline evaluation.  相似文献   
84.
The agreement between self-reported and objective estimates of activity energy expenditure was evaluated in adolescents by age, sex, and weight status. Altogether, 403 participants (217 females, 186 males) aged 13-16 years completed a 3-day physical activity diary and wore a GT1M accelerometer on the same days. Partial correlations (controlling for body mass) were used to determine associations between estimated activity energy expenditure (kcal · min(-1)) from the diary and accelerometry. Differences in the magnitude of the correlations were examined using Fisher's r to z transformations. Bland-Altman procedures were used to determine concordance between the self-reported and objective estimates. Partial correlations between assessments of activity energy expenditure (kcal · min(-1)) did not differ significantly by age (13-14 years: r = 0.41; 15-16 years: r = 0.42) or weight status (normal weight: r = 0.42; overweight: r = 0.39). The magnitude of the association was significantly affected by sex (Δr = 0.11; P < 0.05). The agreement was significantly higher in males than in females. The relationship between activity energy expenditure assessed by the objective method and the 3-day diary was moderate (controlling for weight, correlations ranged between 0.33 and 0.44). However, the 3-day diary revealed less agreement in specific group analyses; it markedly underestimated activity energy expenditure in overweight/obese and older adolescents. The assessment of activity energy expenditure is complex and may require a combination of methods.  相似文献   
85.
The purpose of this study was to examine whether the relationships between contextual factors (i.e., autonomy-supportive vs. controlling coaching style) and person factors (i.e., autonomous vs. controlled motivation) outlined in self-determination theory (SDT) were related to prosocial and antisocial behaviors in sport. We also investigated moral disengagement as a mediator of these relationships. Athletes' (n = 292, M = 19.53 years) responses largely supported our SDT-derived hypotheses. Results indicated that an autonomy-supportive coaching style was associated with prosocial behavior toward teammates; this relationship was mediated by autonomous motivation. Controlled motivation was associated with antisocial behavior toward teammates and antisocial behavior toward opponents, and these two relationships were mediated by moral disengagement. The results provide support for research investigating the effect of autonomy-supportive coaching interventions on athletes' prosocial and antisocial behavior.  相似文献   
86.
International Journal of Science and Mathematics Education - This research study investigated conceptions about buoyancy held by 55 elementary preservice teachers enrolled in a science methods...  相似文献   
87.
Objective:The primary objective of this study was to determine how community college health sciences librarians perceive their proficiencies in the essential skills, knowledge, and abilities necessary for the practice of a health information professional as defined by the Medical Library Association (MLA) Competencies for Lifelong Learning and Professional Success. A secondary objective was to determine their current level of engagement with the professional community and identify barriers to further professional development.Methods:A survey was posted to various email discussion lists, and volunteer follow-up interviews were conducted.Results:The survey was completed by seventy-five community college health sciences librarians, and seven follow-up interviews were performed. Survey results indicated that community college health sciences librarians perceived themselves as having intermediate or advanced intermediate proficiency in the six MLA competencies. Survey and interview results indicated that community college health sciences librarians were engaged with the profession and faced the same barriers to continued professional development and continued education as other academic librarians.Conclusion:The results affirm that community college librarians who are responsible for collections and services in the health sciences meet the MLA competencies, which fills a gap in the literature regarding how these librarians develop professional competencies and are involved in professional associations. The results suggest that community college librarians can improve their skill levels by continuing their education and following trends in the literature.  相似文献   
88.
In this study, we investigated how students used a drawing tool to visualize their ideas of chemical reaction processes. We interviewed 30 students using thinking-aloud and retrospective methods and provided them with a drawing tool. We identified four types of connections the students made as they used the tool: drawing on existing knowledge, incorporating dynamic aspects of chemical processes, linking a visualization to the associated chemical phenomenon, and connecting between the visualization and chemistry concepts. We also compared students who were able to create dynamic visualizations with those who only created static visualizations. The results indicated a relationship between students constructing a dynamic view of chemical reaction processes and their understanding of chemical reactions. This study provides insights into the use of visualizations to support instruction and assessment to facilitate students’ integrated understanding of chemical reactions.  相似文献   
89.
Suicidal and help‐seeking behaviors of students of color remain a significant problem on college campuses. Self‐reported suicidal experiences and help‐seeking behavior of diverse students are examined on the basis of results from a national survey of college student mental health. The results suggest significant differences in the expression of suicidal thoughts and behavior across racial and ethnic groups and different experiences in their referral for, and utilization of, professional help.  相似文献   
90.
Private companies and government agencies are now creating and tapping into vastly more data than ever before. These data flows include enormous amounts of personal information and raise questions about privacy and intellectual policy that could have profound impacts on our lives. While data collection and creation are nearly ubiquitous, the instruments of collection and analysis are often hidden in order to track more natural behavior. Recent revelations of massive governmental data collection offer the country, and librarians in particular, an opportunity to discuss and question the societal implications of “Big Data,” and the policies that govern them.  相似文献   
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