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181.
Abstract

Since 1947, distance education in Mexico has had an important role for nonconventional populations. Considering that distance education is a heterogeneous and dynamic field, it is important to reflect on the need to improve quality as measured by our own standards. With that perspective in mind, a national meeting was organized to start a self‐diagnosis in which quality and access were the main concerns. Five hundred and twenty specialists from fifty‐one institutions participated in a national interactive synchronous meeting held in four regions. As a result of the meeting, thirty‐five criteria and 230 parameters of quality were established. The main conclusion of the meeting refers to the need for the elaboration of our own indicators for open and distance education.  相似文献   
182.
The objective of this paper is to measure the efficiency of high schools in Tunisia. We use a statistical data envelopment analysis (DEA)-bootstrap approach with quasi-fixed inputs to estimate the precision of our measure. To do so, we developed a statistical model serving as the foundation of the data generation process (DGP). The DGP is constructed such that we can implement both smooth homogeneous and heterogeneous bootstrap methods. Bootstrap simulations were used to estimate and correct the bias, and to construct confidence intervals for the efficiency measures. The simulation results show that the efficiency measures are subject to sampling variations. The adjusted measure reveals that high schools with residence services would have to give up less than 12.1% of their resources on average to be efficient.  相似文献   
183.
This paper provides a first approach to the history of Ibérica, one of the most important popular science magazines published in Spain before the Civil War. Founded in 1914 by members of the Society of Jesus based at the Ebro Observatory, Ibérica reached a weekly circulation of about 10,000 in the mid 1920s, and was instrumental in extending science education in Jesuit education facilities and in developing a “reactionary modernist” culture that embraced Catholicism and modernisation. By focusing on its coverage of radioactivity and the radium industry, the article aims to examine the magazine’s popularising style and ideology, and to determine its role in the debates regarding the cultural value of science in the first decades of twentieth century Spain.  相似文献   
184.
In this paper we present a new methodology for detecting differential item functioning (DIF). We introduce a DIF model, called the random item mixture (RIM), that is based on a Rasch model with random item difficulties (besides the common random person abilities). In addition, a mixture model is assumed for the item difficulties such that the items may belong to one of two classes: a DIF or a non-DIF class. The crucial difference between the DIF class and the non-DIF class is that the item difficulties in the DIF class may differ according to the observed person groups while they are equal across the person groups for the items from the non-DIF class. Statistical inference for the RIM is carried out in a Bayesian framework. The performance of the RIM is evaluated using a simulation study in which it is compared with traditional procedures, like the likelihood ratio test, the Mantel-Haenszel procedure and the standardized p -DIF procedure. In this comparison, the RIM performs better than the other methods. Finally, the usefulness of the model is also demonstrated on a real life data set.  相似文献   
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This study analyzes publishing patterns of the staff of the University of Ibadan College of Medicine, Nigeria, based on a bibliography prepared by the authors. Data-gathering for the bibliography is described. An analysis is made of journals staff published in for the period 1961-1980, focusing on changes in journal order rank, publishing locations, and subject spread. A ranked list of the leading journals for the period 1976-1980 is given, showing the importance of local publishing and pointing to the need for local indexing.  相似文献   
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The aim of this study was to assess the effect of stress on a previously acquired motor coordination. Following a longitudinal learning experiment, four participants performed oscillations on a ski simulator, either in normal or stressful conditions. The results showed that the amplitude of the oscillations decreased under stress, but no significant effect was seen regarding coordination, suggesting the strong resistance to stress of overlearned behaviour. Nevertheless, for one participant, a transient regression towards a former stage of learning was observed. This result was consistent with the regression hypothesis formulated by Fuchs (1962).  相似文献   
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