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71.
Research on teaching in Physical Education (RT-PE) comprises a great deal of complex phenomena. These can be understood at a more profound level by using mixed methods research approaches (MMR). Hence, the aim of this paper is to analyze potentials and limitations of mixed methods research in RT-PE, also trying to generate an additional value for MMR.  相似文献   
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This paper exploits discontinuities and randomness in the college admissions in Sweden in 1982, to estimate the economic return to college in the 1990s. At the time, college admissions were highly selective and applicants were ranked with respect to their formal merits. Admissions were given to those ranked higher than some threshold value. At the margin, applicants were sometimes randomly assigned to college. Exploiting this Regression-Discontinuity design, individuals who were admitted in 1982 are estimated to have about 0.20 years longer college education in 1996. However, the earnings effects for applicants at the margin of admission are insignificant. Controlling for the college admission determinants, the OLS-estimates of the return to college is 1.4 percent in 1991–96. The IV-estimates are not significantly different from the OLS counterparts.  相似文献   
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Psychological factors behind incidental information acquisition   总被引:1,自引:0,他引:1  
This paper discusses incidental information acquisition in the light of psychological aspects. A theoretical introduction is followed by an account of three research projects where incidental information acquisition was related to personality traits, approaches to studying, and emotions. The respondents were grades 6–12, master's thesis, and mature library and information science (LIS) students representing an age range of 12–53 years. An energetic personality, high motivation, and positive emotionality were shown to enhance likelihood for incidental acquisition, while low motivation, stress, and insecurity reduced receptivity.  相似文献   
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Information Retrieval systems typically sort the result with respect to document retrieval status values (RSV). According to the Probability Ranking Principle, this ranking ensures optimum retrieval quality if the RSVs are monotonously increasing with the probabilities of relevance (as e.g. for probabilistic IR models). However, advanced applications like filtering or distributed retrieval require estimates of the actual probability of relevance. The relationship between the RSV of a document and its probability of relevance can be described by a normalisation function which maps the retrieval status value onto the probability of relevance (mapping functions). In this paper, we explore the use of linear and logistic mapping functions for different retrieval methods. In a series of upper-bound experiments, we compare the approximation quality of the different mapping functions. We also investigate the effect on the resulting retrieval quality in distributed retrieval (only merging, without resource selection). These experiments show that good estimates of the actual probability of relevance can be achieved, and that the logistic model outperforms the linear one. Retrieval quality for distributed retrieval is only slightly improved by using the logistic function.  相似文献   
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