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51.
The impact of misspecifying covariance matrices at the second and third levels of the three-level model is evaluated. Results indicate that ignoring existing covariance has no effect on the treatment effect estimate. In addition, the between-case variance estimates are unbiased when covariance is either modeled or ignored. If the research interest lies in the between-study variance estimate, including at least 30 studies is warranted. Modeling covariance does not result in less biased between-study variance estimates as the between-study covariance estimate is biased. When the research interest lies in the between-case covariance, the model including covariance results in unbiased between-case variance estimates. The three-level model appears to be less appropriate for estimating between-study variance if fewer than 30 studies are included.  相似文献   
52.
Reforms in engineering education have caused a shift from the traditional stand-alone course in technical communication for Engineering students towards communication training integrated in courses and design projects that allows students to develop four layers of competence. This shift creates opportunities for realistic and situated learning, but offers challenges for assessment of communication competence at student, course and program levels. On the basis of a detailed definition of communicative competence, three formats for integrated communication training are described: Linked to design projects, integrated in design projects and integrated at program level. Assessment of communication competence in these formats is constrained by their characteristics with regard to student motivation, individual and group work, and situated learning.  相似文献   
53.
This article considers the transmission of knowledge in higher education. It takes the metaphor of the music industry that pre‐selects the music people can buy. The sales potential is the leading principle in the selection process. Often the small producer is excluded because his or her music is not of commercial interest. The end‐customer does not know what he or she is missing because he or she has never heard the music. It is to be feared that a similar market principle will also influence the selection of knowledge and affect the capacity of higher education institutions to freely generate and transmit new knowledge. The globalization of higher education risks homogenizing the cultural traditions of the non‐Western world through a process of Western cultural domination. On the other hand, the Internet, via open source software like LINUX, might serve to democratize higher education and allow greater grassroots input.  相似文献   
54.
Purpose: To describe the results of showing farmer learning videos through different types of volunteers.

Design/Methodology/Approach: Semi-structured interviews with volunteers from different occupational groups in Bangladesh, and a phone survey with 227 respondents.

Findings: Each occupational group acted differently. Shop keepers, tillage service providers, agricultural input and machine dealers reached fairly small audiences. Tea stall owners had large, male audiences. Non-governmental organisations and community-based organisations, reached more women. The cable TV (dish-line) operators showed the videos on local TV, but some were reluctant to do so again. The Union Information Service Centres showed the videos and reached women viewers. Half of the official government extension agents surveyed also showed the videos publically.

Practical Implication: This video featured maize, wheat and rice seeding machinery. Because the machinery is complex and requires hands-on training, this first video aimed to expose tillage and sowing service providers and farmers to the machinery, without trying to teach them how to use it. But some farmers were so interested that they watched the video many times to learn more about the equipment. Before farmers and service providers decide to buy machinery for direct seeding, they still want to see and learn from demonstration plantings, to examine first-hand how the crop behaves when planted with the new equipment.

Originality/Value: Video can be an effective way of sharing high-quality information with a large audience, if properly distributed.  相似文献   

55.
In 671 mother–child (49% male) pairs from an epidemiological birth cohort, we investigated (a) prospective associations between DNA methylation (at birth) and trajectories (ages 7–13) of oppositional defiant disorder (ODD), and the ODD subdimensions of irritable and headstrong; (b) common biological pathways, indexed by DNA methylation, between ODD trajectories and attention deficit hyperactivity disorder (ADHD); (c) genetic influence on DNA methylation; and (d) prenatal risk exposure associations. Methylome‐wide significant associations were identified for the ODD and headstrong, but not for irritable. Overlap analysis indicated biological correlates between ODD, headstrong, and ADHD. DNA methylation in ODD and headstrong was (to a degree) genetically influenced. DNA methylation associated with prenatal risk exposures of maternal anxiety (headstrong) and cigarette smoking (ODD and headstrong).  相似文献   
56.
Abstract

To foster lifelong learning skills, we need new didactic approaches with aligned assessment methods. Therefore, we investigated whether the outcomes of a project assignment show a different relation to learning strategies than a longitudinal knowledge-based assessment. We studied learning strategies of first year students of medicine and biomedical sciences (n?=?248) and performed hierarchical regression analyses for the learning strategies and grades of the longitudinal knowledge-based test and project assignment. Scores of students, measured with the Motivated Strategies for Learning Questionnaire (Likert scale 1–7), were relatively low for critical thinking (3.53), compared to rehearsal (4.40), elaboration (4.82), organisation (4.69) and metacognitive self-regulation (4.33). Knowledge based tests showed a significant relation to elaboration (p?<?0.01). For the project-based assessment, we did not find a significant relation to any learning strategy (p?=?0.074). Explained variance of the grades was low for all learning strategies (R2 < 0.043). Different types of assessment did not discriminate between students with high or low scores on learning strategies associated with lifelong learning. An explanation is that the curriculum is not aligned with assessment, or students do not benefit in terms of grades. We conclude that, if assessment is to drive lifelong learning skills, this is not self-evident.  相似文献   
57.
This study examines the post-M&A innovative performance of acquiring firms in four major high-tech sectors. Non-technological M&As appear to have a negative impact on the acquiring firm's post-M&A innovative performance. With respect to technological M&As, a large relative size of the acquired knowledge base reduces the innovative performance of the acquiring firm. The absolute size of the acquired knowledge base only has a positive effect during the first couple of years after which the effect turns around and we see a negative effect on the innovative performance of the acquiring firm. The relatedness between the acquired and acquiring firms’ knowledge bases has a curvilinear impact on the acquiring firm's innovative performance. This indicates that companies should target M&A ‘partners’ that are neither too unrelated nor too similar in terms of their knowledge base.  相似文献   
58.
Infant joint attention has been observed to be related to social-emotional outcomes in at-risk children. To address whether this relation is also evident in typically developing children, 52 children were tested at 12, 15, 24, and 30 months to examine associations between infant joint attention and social outcomes. Twelve-month initiating and responding to joint attention were related to 30-month social competence and externalizing behavior, even when accounting for 15-month temperament ratings, 24-month cognition and language, and demographic variables. These results suggest that, in addition to associations with language and cognition, infant joint attention reflects robust aspects of development that are related to individual differences in the emergence of social and behavioral competence in childhood.  相似文献   
59.
Age differences in decision making indicate that children fail to anticipate outcomes of their decisions. Using heart rate and skin conductance analyses, we tested whether developmental changes in decision making are associated with (a) a failure to process outcomes of decisions, or (b) a failure to anticipate future outcomes of decisions. Children aged 8-10, 12-14, and 16-18 years performed the Hungry Donkey task, a child version of the Iowa Gambling Task, while heart rate and skin conductance activity were continuously recorded. Children aged 16-18 learned to make advantageous choices over task blocks faster than the two younger age groups. Age differences were present for anticipation-related autonomic activity but not outcome-related autonomic activity. The results are interpreted vis-à-vis models of prefrontal cortex maturation.  相似文献   
60.
This study examined developmental trends in object and spatial working memory (WM) using heart rate (HR) to provide an index of covert cognitive processes. Participants in 4 age groups (6-7, 9-10, 11-12, 18-26, n=20 each) performed object and spatial WM tasks, in which each trial was followed by feedback. Spatial WM task performance reached adult levels before object WM task performance. The differential developmental trends for object and spatial WM found in this study are taken to suggest that these WM components are separable. Negative performance feedback elicited HR slowing that was more pronounced for adults than for children. The development of performance monitoring as indexed by covert HR slowing following performance feedback contributes to WM performance.  相似文献   
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