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ABSTRACTWhen searching for information on the Internet, it can be stored in a bookmarking system. The ability to organize this information in such a system depends on one’s own prior knowledge to create an appropriate classification scheme. Providing a classification system for bookmarks might support people with low prior knowledge. Even though different bookmarking systems exist, hierarchical menus and tagging are being most widely used. In the current exploratory study with 95 ninth-grade students, a 2 × 2 between-subjects design was used to investigate the influence of providing classification support (or not) for either a tagging or a hierarchical system. Results showed that despite the low familiarity with tagging systems, using a hierarchical system is not necessarily a better approach than using a tagging system to organize previously found information. Rather, a tagging system seems to yield storage of fewer but higher-quality information sources. The most important conclusion is that, despite the low familiarity with tagging systems, using a hierarchical system was not beneficial over using a tagging system to organize previously found information. 相似文献
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B R Wilson H W Olson H A Sprague W D Van Huss H J Montoye 《Research quarterly for exercise and sport》1990,61(1):1-6
A longitudinal study was conducted on 398 athletes and 369 nonathletes who were born before 1920 and attended Michigan State University. The subjects were compared to determine if intercollegiate athletic competition accounts for significant variation in longevity when considered with somatotype. Because some of the subjects were still alive at the time of the study, the BMDP Statistical Software was used to do a survival analysis with covariates. Preliminary comparisons considered the differences in somatotype between athletes and nonathletes. Two sample t-tests indicated that athletes were more mesomorphic and less ectomorphic (p less than .05) than nonathletes. When comparing the relationship between somatotype and longevity, the pooled data of athletes and nonathletes indicated that endomorphs were shorter lived than the other three comparison groups. When only the athletes were considered, similar results were found. However, the nonathlete group exhibited differences only between the mesomorphic and endomorphic groups. The endomorphs were shorter lived. Longevity was examined by using the Cox proportional hazards regression method with somatotype and athlete/nonathlete status as covariates. Somatotype, by itself, was found to be significantly related to longevity, (p less than .001). Athletic status was not significantly related to longevity, either by itself or when entered into the model with somatotype. 相似文献
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An alternative format for presentation of the MEDLINE Update is presented. Utilization of a statewide closed-circuit television network is time-saving and cost-effective for the audience. Differences in and audience response to this alternative programming are described. 相似文献
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Bart Van Looy Paolo LandoniJulie Callaert Bruno van PottelsbergheEleftherios Sapsalis Koenraad Debackere 《Research Policy》2011,40(4):553-564
The phenomenon of entrepreneurial universities has received considerable attention over the last decades. An entrepreneurial orientation by academia might put regions and nations in an advantageous position in emerging knowledge-intensive fields of economic activity. At the same time, such entrepreneurial orientation requires reconciliation with the scientific missions of academia. Large-scale empirical research on antecedents of the entrepreneurial effectiveness of universities is scarce. This contribution examines the extent to which scientific productivity affect entrepreneurial effectiveness, taking into account the size of universities and the presence of disciplines, as well as the R&D intensity of the regional business environment (BERD). In addition, we assess the occurrence of trade-offs between different transfer mechanisms (contract research, patenting and spin off activity). The data used pertain to 105 European universities. Our findings reveal that scientific productivity is positively associated with entrepreneurial effectiveness. Trade-offs between transfer mechanisms do not reveal themselves; on the contrary, contract research and spin off activities tend to facilitate each other. Limitations and implications for future research are discussed. 相似文献
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Bibliometric mapping of computer and information ethics 总被引:1,自引:0,他引:1
Richard Heersmink Jeroen van den Hoven Nees Jan van Eck Jan van den Berg 《Ethics and Information Technology》2011,13(3):241-249
This paper presents the first bibliometric mapping analysis of the field of computer and information ethics (C&IE). It provides a map of the relations between 400 key terms in the field. This term map can be used to get an overview of concepts and topics in the field and to identify relations between information and communication technology concepts on the one hand and ethical concepts on the other hand. To produce the term map, a data set of over thousand articles published in leading journals and conference proceedings in the C&IE field was constructed. With the help of various computer algorithms, key terms were identified in the titles and abstracts of the articles and co-occurrence frequencies of these key terms were calculated. Based on the co-occurrence frequencies, the term map was constructed. This was done using a computer program called VOSviewer. The term map provides a visual representation of the C&IE field and, more specifically, of the organization of the field around three main concepts, namely privacy, ethics, and the Internet. 相似文献
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