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181.
Estimating treatment effects for subgroups defined by posttreatment behavior (i.e., estimating causal effects in a principal stratification framework) can be technically challenging and heavily reliant on strong assumptions. We investigate an alternative path: using bounds to identify ranges of possible effects that are consistent with the data. This simple approach relies on fewer assumptions and yet can result in policy-relevant findings. As we show, even moderately predictive covariates can be used to substantially tighten bounds in a straightforward manner. Via simulation, we demonstrate which types of covariates are maximally beneficial. We conclude with an analysis of a multisite experimental study of Early College High Schools. When examining the program's impact on students completing the ninth grade “on-track” for college, we find little impact for ECHS students who would otherwise attend a high-quality high school, but substantial effects for those who would not. This suggests a potential benefit in expanding these programs in areas primarily served by lower quality schools.  相似文献   
182.
Building a metacognitive model of reflection   总被引:2,自引:0,他引:2  
An increased value is being placed on quality teaching in higher education. An important step in developing approaches to better instruction is understanding how those who are successful go about improving their teaching. Thus, several years ago we undertook a program of research in which the concept of reflection provided the frame of reference. We envisaged reflection as a process of formative evaluation, and also saw links between reflection and metacognition. What we have documented and analyzed in detail are the reflective processes of six university professors in their day-to-day planning, instructing and evaluating of learners. The result is a metacognitive model and coding scheme that operationalize the process of reflection. Both provide a language for describing reflection and therefore a way to think about how to improve teaching. In this paper, we describe the research and the model and the contributions they make to our understanding of teacher thinking in higher education.  相似文献   
183.
This paper documents the effectiveness of a substitute activity in decreasing the frequency of eye poking in a 3‐year‐old nonretarded visually impaired child who was involved in a highly participatory, full‐day reading program with four sighted classmates. Following 49 days of training, eye poking had been eliminated, and the subject was able to read 25 word cards. Elements to consider when selecting a substitute activity to interrupt an established self‐stimulating behaviour such as eye poking are discussed.  相似文献   
184.
The purpose of this study is to explore key factors that impact the college transition of aspiring underrepresented minority students in the biomedical and behavioral sciences, in comparison with White, Asian students and non-science minority students. We examined successful management of the academic environment and sense of belonging during the first college year. Longitudinal data were derived from the Higher Education Research Institute’s (HERI) 2004 Cooperative Institutional Research Program (CIRP) Freshman Survey and the 2005 Your First College Year (YFCY) Survey. Using a reformulation of the integration model (Nora, Barlow, and Crisp, 2005), we find concerns about college financing, negotiating family support and responsibility, and campus racial dynamics (perceived and behavioral) affect student adjustment and sense of integration in the first year. This study was made possible by the support of the National Institute of General Medical Sciences, NIH Grant Number 1 RO1 GMO71968-01. This independent research and the views expressed here do not indicate endorsement by the sponsor.  相似文献   
185.
Editorial     
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186.
A new site-specific nutrient management approach was developed to break the apparent attainable yield barrier of 6 t·ha−1 in the double rice cropping system of Zhejiang. On-farm experiments involving 21 rice-growing farmer families and NPK long-term experiments commenced in 1997 in the central part of Zhejiang Province to assess the status of soil fertility and productivity under intensive rice-rice cropping. A new site-specific nutrient management (SSNM) approach has been developed for this studied area. Field-specific fertilizer recommendations are calculated considering indigenous nutrient supply, reasonable grain yield targets and corresponding nutrient demand, nutrient balance and nutrient use efficiency, as well as socio-economic factors. The agronomic performance of SSNM was tested against the farmer's fertilizer practice (FFP) in four 1998–1999 cropping seasons. Across seasons and years, SSNM consistently increased plant nutrient uptake, grain yield and profit by about 10%–15% compared to the FFP. Yield levels of 7.5 t·ha−1 or more seem achievable and sustainable through introduction of SSNM and improved extension services in Zhejiang Province. Project supported by the International Fertilizer Industry Association(IFA), the Potash and Phosphate Institute, Canada (PPIC), and International Potash Institute(IPI).  相似文献   
187.
188.
Adolescents (n=43) previously diagnosed as dyslexic/reading disabled had markedly lower IQ scores on the newly standardized Wechsler Intelligence Scale for Children (WISC-III) than on the earlier administered WISC-R. The declines for Verbal, Performance, and Full Scale IQs were 10, 12, and 11 points, respectively, which were twice as great as in a subset of the standardization sample given both versions of the WISC. The adolescents did not show a significant decline in standard scores from the Wide Range Achievement Test (Level I to Level II). However, only two subjects had current reading and spelling standard scores above the 25th percentile. The impact of lower WISC-III IQs on guidelines for classification of students as learning disabled is discussed.  相似文献   
189.
A learning cycle approach to undergraduate instruction was implemented in a variety of subjects in the liberal arts and sciences. The students in the experimental program were typical representatives of an institution with liberal admissions policies. Significant gains were made in critical thinking and cognitive skill development by the experimental group. Additionally, retention of the experimental group was improved. Gains of this sort have the potential to rekindle hope in college faculties that some of the traditional goals of higher education that center on critical thinking and cognitive skill development need not be abandoned in institutions with liberal admissions policies.  相似文献   
190.
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