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21.
Olivier Chapelle Shihao Ji Ciya Liao Emre Velipasaoglu Larry Lai Su-Lin Wu 《Information Retrieval》2011,14(6):572-592
We study the problem of web search result diversification in the case where intent based relevance scores are available. A
diversified search result will hopefully satisfy the information need of user-L.s who may have different intents. In this
context, we first analyze the properties of an intent-based metric, ERR-IA, to measure relevance and diversity altogether.
We argue that this is a better metric than some previously proposed intent aware metrics and show that it has a better correlation
with abandonment rate. We then propose an algorithm to rerank web search results based on optimizing an objective function
corresponding to this metric and evaluate it on shopping related queries. 相似文献
22.
This paper introduces a new way of evaluating instructional strategies by using computers. Two basic theories, instructivism and constructivism, are discussed and critically evaluated in terms of their effectiveness in conceptual learning. Despite the current popularity of constructivism, the radical form of it is criticized in this paper. The advantages and limitations of these two approaches, especially the radical forms of constructivism, are outlined. After borrowing some ideas from other effective conceptual change models, an integrative model for conceptual learning (the Inventive Model) is introduced. Two versions of multimedia physics software are developed by the authors. The first version is based on the Inventive Model and the second version based on a radical constructivist model. The effectiveness of the Inventive Model was compared with the radical constructivist approach and conventional science instruction. Students' log files were analyzed to investigate the nature and the processes of the conceptual change. A conceptual test and a knowledge test were used to compare the groups. The quantitative results showed the superiority of the Inventive Model over the other models in conceptual learning and the superiority of conventional instruction in learning the basic knowledge. The qualitative analysis showed that only the Inventive Model lead to coherent conceptual learning. It was concluded that the process of conceptual change is gradual and continuous. Analysis of students' log files revealed no moments of dramatic change in students' conceptions. 相似文献
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This article advocates the use of simple data sets to help students gain a good intuitive grasp of ANOVA concepts. 相似文献
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27.
Larry E. Stanfel 《Information processing & management》1983,19(1):37-50
Given the difficulty of designing and creating information systems of many components and interconnections, it is commonplace to find these tasks accomplished by means of a partition into subsystems. Later the distinct subsystems are made to interface with one another and an overall system is achieved. The purpose of the present paper is to point out the availability of methods for effecting the partition in optimal or approximately optimal ways. Clustering algorithms for the specific case of information systems are obtained and exemplified. 相似文献
28.
We explore the feasibility of automatically identifying sentences in different MEDLINE abstracts that are related in meaning.
We compared traditional vector space models with machine learning methods for detecting relatedness, and found that machine
learning was superior. The Huber method, a variant of Support Vector Machines which minimizes the modified Huber loss function,
achieves 73% precision when the score cutoff is set high enough to identify about one related sentence per abstract on average.
We illustrate how an abstract viewed in PubMed might be modified to present the related sentences found in other abstracts
by this automatic procedure. 相似文献
29.
Shu-Mey Yu Larry D. Yore 《International Journal of Science and Mathematics Education》2013,11(5):1233-1254
The purpose of this study was to investigate the quality, evolution, and position of university students’ argumentation about organic agriculture over a 4-week argument–critique–argument e-learning experience embedded in a first year university biology course. The participants (N??=??43) were classified into three groups based on their epistemological views. Data collected from individual arguments, group deliberations, and individual critiques were coded and analyzed to establish the quality and evolution of argumentation. Results indicated significant improvement in the quality of their justifications between the first and second arguments. Post-hoc comparison of epistemological groups indicated that the more constructivist-oriented students had a greater significant evolution of their justifications than the more empiricist-oriented students, but there was no significant main effect for epistemological orientation. Qualitative analysis of the intervening critiques indicated that some students incorporated or used other students’ arguments or counter-arguments to change their position or to enhance the justification of their original position on organic agriculture, while others appeared to be locked into a confirmation-bias stance and search for evidence that supported their original position and disregarded contradictory evidence. 相似文献
30.
The primary purpose of this study was to examine the relation between full - time or part - time instructor status and college student retention and academic performance in sequential courses . Results indicate that for either developmental or regular courses, college students who take the first course in a sequence from a part - time instructor , and who take the second course in the sequence from a full - time instructor seem underprepared for the second course. By contrast to students experiencing other instructor status combinations (part - time / part - time , full - time / part - time , or full - time / full - time), these students are significantly less likely to either complete or achieve a grade of "C" or better in the second course. Sequential course instructor status, therefore, seems to be a predictor of college student success. Implications for practice pertaining to further research, college students, and institutions are discussed. 相似文献