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Online supervision mainly focuses on written communication and electronic drafts, while offline supervision comprises physical and social clues, verbal communication, and drafts of texts. This article focuses on supervisors’ written online communication about drafts of undergraduate student dissertations. Theoretically, these utterances form part of the communicative exchanges performed in the practice of supervision. This means that supervision is an emergent phenomenon that relates to its past, current, and future states. The setting was a dissertation course within a bachelor programme in behavioural science. The data consists of 423 utterances from four supervisors. The utterances were analysed and categorised, and the results show different qualities and degrees of identifications in the supervisors’ communicated utterances. The study shows that the quality of supervisors’ utterances embraces the difference between the application of comments, points of view, instructions, and questions. This implicates the importance of supervisors’ awareness of the nature and the combination of their utterances if they want to increase the student autonomy when supervising online. 相似文献
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Analyzing examinees’ responses using cognitive diagnostic models (CDMs) has the advantage of providing diagnostic information. To ensure the validity of the results from these models, differential item functioning (DIF) in CDMs needs to be investigated. In this article, the Wald test is proposed to examine DIF in the context of CDMs. This study explored the effectiveness of the Wald test in detecting both uniform and nonuniform DIF in the DINA model through a simulation study. Results of this study suggest that for relatively discriminating items, the Wald test had Type I error rates close to the nominal level. Moreover, its viability was underscored by the medium to high power rates for most investigated DIF types when DIF size was large. Furthermore, the performance of the Wald test in detecting uniform DIF was compared to that of the traditional Mantel‐Haenszel (MH) and SIBTEST procedures. The results of the comparison study showed that the Wald test was comparable to or outperformed the MH and SIBTEST procedures. Finally, the strengths and limitations of the proposed method and suggestions for future studies are discussed. 相似文献
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The concept of an “information space” provides a powerful metaphor for guiding the design of interactive retrieval systems. We present a case study of related article search, a browsing tool designed to help users navigate the information space defined by results of the PubMed® search engine. This feature leverages content-similarity links that tie MEDLINE® citations together in a vast document network. We examine the effectiveness of related article search from two perspectives: a topological analysis of networks generated from information needs represented in the TREC 2005 genomics track and a query log analysis of real PubMed users. Together, data suggest that related article search is a useful feature and that browsing related articles has become an integral part of how users interact with PubMed. 相似文献
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Jimmy?Lin Andrew?TrotmanEmail authorView author&#;s OrcID profile 《Information Retrieval》2017,20(3):199-220
This paper explores the performance of top k document retrieval with score-at-a-time query evaluation on impact-ordered indexes in main memory. To better understand execution efficiency in the context of modern processor architectures, we examine the role of index compression on query evaluation latency. Experiments include compressing postings with variable byte encoding, Simple-8b, variants of the QMX compression scheme, as well as a condition that is less often considered—no compression. Across four web test collections, we find that the highest query evaluation speed is achieved by simply leaving the postings lists uncompressed, although the performance advantage over a state-of-the-art compression scheme is relatively small and the index is considerably larger. We explain this finding in terms of the design of modern processor architectures: Index segments with high impact scores are usually short and inherently benefit from cache locality. Index segments with lower impact scores may be quite long, but modern architectures have sufficient memory bandwidth (coupled with prefetching) to “keep up” with the processor. Our results highlight the importance of “architecture affinity” when designing high-performance search engines. 相似文献
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Jimmy Jaldemark 《Education and Information Technologies》2008,13(2):129-146
This paper focuses on written utterances in online settings of higher education. It concerns the constitution of the initiation,
turn taking and the steering of exchanges of utterances; and it describes these patterns in terms of different genres. The
study also concerns participation in higher education and, specifically, participation in educational settings where students
and teachers rarely meet face-to-face. Their participation is thus dependant on written utterances in online settings. Overall,
this paper discusses constitutive aspects of these written utterances. The educational communication between students and
teachers embraced both student- and teacher-centered genres. The distinction between these two genres relates to the functionality
of the utterances, the main metaphor for learning and the responsibilities for the communication taken by students and teachers.
The emergence of these genres seems to be affected by interplay between the composition of the study-groups, the structure
of the task and other aspects of participation through online settings. 相似文献
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Jimmy Stahr 《Educational Media International》2013,50(4):3-4
During the fifties and the sixties there had been a pronounced increase in the interest of pre-school children and their development. This interest has been encouraging as well as frightening. 相似文献
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