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981.
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
982.
983.
Business opportunities in international markets are largely determined by accessibility, transparency, and legal frameworks
fair to all parties concerned. Arab book markets in principle offer a tremendous potential with more than 300 million readers
sharing one common language. Besides unsolved censorship issues, problems with money collection, and differing regulations,
however, the lack of a uniform book distribution system is the most critical hurdle for the development of a common Arabic
book market. Most importantly, there is no comprehensive database containing accurate content briefs, background information
on authors, ISBN numbers, and publisher company information as well as all relevant commercial data such as book prices, weight,
logistics terms, and availability. Authors and publishers are hard hit as they often need to organize book transportation,
delivery, and invoice collection on their own. At present, “selling book fairs” in the Arab world—with the exception of Abu
Dhabi International Book Fair—present themselves as crowded book bazaars rather than executive meeting points. The authors
of the article, however, are anticipating change: New distribution initiatives will soon interlink regional Arabic markets
and create unique growth and profit opportunities. 相似文献
984.
985.
Andrew Weinstein 《Publishing Research Quarterly》2010,26(1):11-15
Forecasts indicate a growing demand for digital content around the world. Converting to digital content can open up countless new revenue possibilities. Adding alternate channels may be worth consideration, but what are the options and what does it take to utilize them effectively? This article explores the opportunities that potentially exist for publishers with content that may be digitized and distributed to global markets. A brief review of the current marketplace is also incorporated, including current players and trends. Finally, an analysis of some of the potential issues, challenges and pitfalls is presented in context of delving into a new international digital content distribution strategy. 相似文献
986.
Bing Bai Jason Weston David Grangier Ronan Collobert Kunihiko Sadamasa Yanjun Qi Olivier Chapelle Kilian Weinberger 《Information Retrieval》2010,13(3):291-314
In this article we present Supervised Semantic Indexing which defines a class of nonlinear (quadratic) models that are discriminatively
trained to directly map from the word content in a query-document or document-document pair to a ranking score. Like Latent
Semantic Indexing (LSI), our models take account of correlations between words (synonymy, polysemy). However, unlike LSI our
models are trained from a supervised signal directly on the ranking task of interest, which we argue is the reason for our
superior results. As the query and target texts are modeled separately, our approach is easily generalized to different retrieval
tasks, such as cross-language retrieval or online advertising placement. Dealing with models on all pairs of words features
is computationally challenging. We propose several improvements to our basic model for addressing this issue, including low
rank (but diagonal preserving) representations, correlated feature hashing and sparsification. We provide an empirical study
of all these methods on retrieval tasks based on Wikipedia documents as well as an Internet advertisement task. We obtain
state-of-the-art performance while providing realistically scalable methods. 相似文献
987.
We evaluated the effects of one year of schoolwide cluster grouping on the academic achievement growth of gifted and non-identified elementary students using a piecewise multilevel growth model. Scores from 186 non-identified and 68 gifted students’ Measures of Academic Progress Reading and Math scores were examined over three school years. In 2008–2009 within-class ability grouping was used. In 2009–2010 schoolwide cluster grouping was implemented. In 2010–2011 students once again were grouped only within classrooms by ability and students identified as gifted were spread across all classrooms at each grade level. Results suggest that schoolwide cluster grouping influenced student performance in the year following its implementation, but only for mathematics and not the area of reading. 相似文献
988.
John K. Lannin Matthew Webb Kathryn Chval Fran Arbaugh Sarah Hicks Cynthia Taylor Rebecca Bruton 《Journal of Mathematics Teacher Education》2013,16(6):403-426
Recent research efforts (Schmidt et al. in The preparation gap: teacher education for middle school mathematics in six countries, MSU Center for Research in Mathematics and Science Education, 2007) demonstrate that teacher development programs in high-performing countries offer experiences that are designed to develop both mathematical knowledge and pedagogical knowledge. However, identifying the nature of the mathematical knowledge and the pedagogical content knowledge (PCK) required for effective teaching remains elusive (Ball et al. in J Teacher Educ 59:389–407, 2008). Building on the initial conceptual framework of Magnusson et al. (Examining pedagogical content knowledge, Kluwer, Dordrecht, pp 95–132, 1999), we examined the PCK development for two beginning middle and secondary mathematics teachers in an alternative certification program. The PCK development of these two individuals varied due to their focus on developing particular aspects of their PCK, with one individual focusing on assessment and student understanding, and the other individual focusing on curricular knowledge. Our findings indicate that these individuals privileged particular aspects of their knowledge, leading to differences in their PCK development. This study provides insight into the specific aspects of PCK that developed through the course of actual instructional practice, providing a lens for future research in this area. 相似文献
989.
Christian Rittelmeyer 《Zeitschrift für Erziehungswissenschaft》2013,16(3):217-231
Transfer research examines how artistic activities can have an impact outside of the realm of art itself. The article concludes that this research can be carried out in a meaningful way, only within the framework of a comprehensive theory of aesthetic education. This theory would encompass the structural analysis of artistic activity, as well as biographical reports about artistic experiences. The elucidation of the concepts or themes relevant to the theory would include the notion of aesthetic experience, the understanding of immediate, aesthetic experiences, the analysis of artistic processes, and the outcomes of scientifically evaluated applications of aesthetic education. 相似文献
990.
This paper addresses potential negative effects of systematic external competence assessment on different levels of the education system. We discuss possible sources of misinterpretations of competence assessment feedback, potential consequences of feedback and assessment for different education stakeholders (teachers, students, and educational administration) as well as negative effects of systematic competence assessment on the culture of teaching and learning. The paper concludes with some reflections on possibilities to prevent or reduce the discussed negative effects. 相似文献