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This single-case-design experiment examined an intervention to decrease bed-sharing in children, ages 2 through 6. Three sessions were conducted with each parent. At the first session, parents described bed-sharing history and began collecting baseline data. At the second session, parents were instructed to employ the intervention. At the third session, parents were interviewed and offered continued support, if needed. Participants included three children who slept with their parents 4 or more nights per week. The intervention resulted in a substantial decrease in bed-sharing behavior for all participants, and parents reported being satisfied with the intervention.  相似文献   
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This article describes a detailed analysis of knowledge building in a problem-based learning group. Knowledge building involves increasing the collective knowledge of a group through social discourse. For knowledge building to occur in the classroom, the teacher needs to create opportunities for constructive discourse in order to support student learning and collective knowledge building. In problem-based learning, students learn through collaborative problem solving and reflecting on their experiences. The setting for this study is a group of second-year medical students working with an expert facilitator. The analysis was designed to understand how the facilitator provided opportunities for knowledge-building discourse and how the learners accomplished collective knowledge building. We examined episodes of knowledge-building discourse, the questions and statements that the students and facilitator generated throughout the tutorial, the change in their understanding of the problem that they were solving, and the collective knowledge that was constructed. The results indicate that the group worked to progressively improve their ideas through engaging in knowledge-building discourse. The facilitator helped support knowledge building through asking open-ended metacognitive questions and catalyzing group progress. Students took responsibility for advancing the group's understanding as they asked many high-level questions and built on each others thinking to construct collaborative explanations. The results of this study provide suggestions for orchestrating knowledge-building discourse.  相似文献   
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To deal with missing data that arise due to participant nonresponse or attrition, methodologists have recommended an “inclusive” strategy where a large set of auxiliary variables are used to inform the missing data process. In practice, the set of possible auxiliary variables is often too large. We propose using principal components analysis (PCA) to reduce the number of possible auxiliary variables to a manageable number. A series of Monte Carlo simulations compared the performance of the inclusive strategy with eight auxiliary variables (inclusive approach) to the PCA strategy using just one principal component derived from the eight original variables (PCA approach). We examined the influence of four independent variables: magnitude of correlations, rate of missing data, missing data mechanism, and sample size on parameter bias, root mean squared error, and confidence interval coverage. Results indicate that the PCA approach results in unbiased parameter estimates and potentially more accuracy than the inclusive approach. We conclude that using the PCA strategy to reduce the number of auxiliary variables is an effective and practical way to reap the benefits of the inclusive strategy in the presence of many possible auxiliary variables.  相似文献   
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