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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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Deborah J. Taub Heather L. Servaty‐Seib Nathan Miles Ji‐Yeon Lee Carrie A. Wachter Morris Susan L. Prieto‐Welch Donald Werden 《Journal of College Counseling》2013,16(1):64-78
Resident assistants (RAs) can serve as important suicide prevention gatekeepers. The purpose of the study was to determine if training improved RAs’ crisis communications skills and suicide‐related knowledge and to determine if the knowledge elements predicted crisis communications skills. New RAs showed significant improvement in all areas from pretest to posttest, whereas returning RAs showed no significant increase in any of the areas. None of the knowledge areas predicted communications skills for either group. 相似文献