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Some sort of reportorial process is necessary for evaluation of undergraduate laboratory work. A variety of methods currently employed are not entirely satisfactory. Ideally, such a process should accomplish its purpose with a minimum expenditure of time and effort and, wherever possible, enhance the educational efficiency of the laboratory. Under certain conditions, verbal communication may be employed to these ends. In addition to more efficient use of time, other results include: more accurate evaluation, increased effectiveness of laboratory problems as teaching devices, and useful training in the use of verbal communication. In other terms, the communication channel between instructor and student may be given greater capacity, less noise, and changed more nearly into a closed loop. 相似文献
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Appropriate intellectual property protection and economic growth in countries at different levels of development 总被引:1,自引:0,他引:1
This paper examines how the role of patents and utility models in innovation and economic growth varies by level of economic development. Using a panel dataset of over 70 countries, we find that patent protection is an important determinant of innovation and that patentable innovations contribute to economic growth in developed countries, but not in developing. Instead, in developing economies, a minor form of intellectual property rights (IPRs) - namely utility models - is conducive to innovation and growth, controlling for other factors. Using Korean firm level data as a case study, we find that utility model innovations contribute to firm performance when firms are technologically lagging and that those minor innovations can be a learning device and thus a stepping stone for developing more patentable inventions later on. Upon reaching higher levels of technological capabilities, firms become more reliant upon patents and less on utility models. Thus the lesson here is that patent protection enhances innovation and economic growth in countries where the capacity to conduct innovative research exists. Where this capacity is weaker, a system that provides incentives to conduct minor, incremental inventions is more conducive to growth. The significance of this paper is to emphasize the importance not just of the strength of IPRs but of the appropriate type of IPRs for economic development. 相似文献
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Walter L. Leite Robert Sandbach Rong Jin Jann W. MacInnes M. Grace-Anne Jackman 《Structural equation modeling》2013,20(3):437-456
Because random assignment is not possible in observational studies, estimates of treatment effects might be biased due to selection on observable and unobservable variables. To strengthen causal inference in longitudinal observational studies of multiple treatments, we present 4 latent growth models for propensity score matched groups, and evaluate their performance with a Monte Carlo simulation study. We found that the 4 models performed similarly with respect to model fit, bias of parameter estimates, Type I error, and power to test the treatment effect. To demonstrate a multigroup latent growth model with dummy treatment indicators, we estimated the effect of students changing schools during elementary school years on their reading and mathematics achievement, using data from the Early Childhood Longitudinal Study Kindergarten Cohort. 相似文献
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Assistant teachers are a ubiquitous yet virtually overlooked part of the early education workforce. Assistant teacher education level and its relationship to various classroom characteristics and the roles lead teachers feel assistants play in classroom management and teaching were examined in a nationally representative sample of 3,191 state-funded prekindergarten classes. Research Findings: Most classrooms had at least 1 paid assistant teacher, and classrooms with multiple assistants were more likely to be in Head Start. Lead teachers in public schools were more likely to have a bachelor's degree or higher, to be paired with an assistant with a high school degree, and to report fewer release hours for planning (alone or shared with assistants) than teachers in Head Start. Hierarchical multiple regression indicated that assistant teachers were rated as most useful to teaching duties when the classroom was in a Head Start setting, when the discrepancy between the lead and assistant teachers’ education was smaller, and when there were more shared release hours for planning. Practice and Policy: Implications focus on future prekindergarten teacher workforce needs, the need for more shared planning time and guidance in its use, and the need for more attention to and support for the training and roles of assistant teachers. 相似文献
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Walter M. Fontane 《College & Undergraduate Libraries》2017,24(1):90-102
There is considerable literature evaluating video tutorials. By the first decade of the twenty-first century, research established that online video tutorials performed as well as traditional face-to-face instruction. However, there is little evidence that students actually viewed the tutorials. This study compares postinstruction assessment quiz scores from one class over four semesters with usage statistics for five video tutorials during the same time frame. The data indicate that students do view the tutorials. However, the results also show that usage statistics, together with quiz scores, declined as students progressed through the five tutorials. Additionally, the study determined that there was no positive correlation between the number of viewings and postviewing assessment scores. 相似文献