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71.
Mauro Rojas Herrera Edleno Silva de Moura Marco Cristo Thomaz Philippe Silva Altigran Soares da Silva 《Information processing & management》2010
Queries submitted to search engines can be classified according to the user goals into three distinct categories: navigational, informational, and transactional. Such classification may be useful, for instance, as additional information for advertisement selection algorithms and for search engine ranking functions, among other possible applications. This paper presents a study about the impact of using several features extracted from the document collection and query logs on the task of automatically identifying the users’ goals behind their queries. We propose the use of new features not previously reported in literature and study their impact on the quality of the query classification task. Further, we study the impact of each feature on different web collections, showing that the choice of the best set of features may change according to the target collection. 相似文献
72.
de Boer J 《Public understanding of science (Bristol, England)》2010,19(6):654-668
New applications of genomics techniques in soil ecology may provide people with fresh insights into the richness of microbial life forms and natural methods to build on the "self-cleaning capacity" of soils. Because genetic modification might also be involved, this paper examines people's judgments about some applications, using a theory on the promotion- or prevention-orientations that they may associate with interventions in the natural world. A prevention-oriented way of thinking was hypothesized to correspond with a preference for more restrictions on a GM application, unless the person appreciates the application's benefits for nature restoration. Survey data agreed with the hypotheses and clarified the way in which people may talk about "nature knows best" or "nature needs a little help". 相似文献
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Sixten Marklund Franz Hilker Marjorie L. Jenkins Franklin Parker Gustav Jahoda M. J. Langeveld Karl Henrik Eriksson Nicholas Hans Gilbert de Landsheere Leslie D. Mclean J. Cambon A. St. Langeland S. Wiegersma Richard F. Goodings J. B. Biggs 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1966,12(2):221-251
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Walter Hahn Helmut Skowronek H. J. Butcher Hans-Martin Müller-Wolf J. C. Cairns Michael Angermaier Maureen Woodhall Ha Wun Sung Oskar Anweiler John A. Smyth Gilbert de Landsheere Gaby Venstermans Erika Voigt Anza Amen Lema David Wolsk Robert O. Berdahl 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1974,20(1):83-107
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Although the importance of high motivation to engage in deliberate practice has been acknowledged, no research has directly tested this hypothesis. Therefore, the present study examined this relation in adolescent elite chess players by means of a questionnaire. In addition, to provide an explanation for dropout among promising chess players, differences in motivation between persistent and dropout chess players were analyzed. Competitiveness and the will to excel proved to be predictors of investments in deliberate practice. Moreover, achievement motivation and chess-specific motivation differed to a certain extent between persisters and dropouts. Our results suggest that motivation to engage in deliberate practice not only contains elements of the will to improve performance, but also of the will to attain exceptional levels of performance. 相似文献