From Retrieval Status Values to Probabilities of Relevance for Advanced IR Applications     

Henrik Nottelmann  Norbert Fuhr 《Information Retrieval》2003,6(3-4):363-388

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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贺巷超 《图书情报工作》1998,42(7):20-22,51

认为现代图书馆与读者发生着多种联系,而距离和距离感是造成与读者隔阂的重要因素。消除读者客观和主观上存在的距离是谋求图书情报事业发展的基本出发点和归宿  相似文献   

�й����׼���ѧ�������ס���������������ڿ�   总被引：14，自引：1，他引：13  

孟连生  丁颖 《图书情报工作》1998,(4):21-24

利用引文分析方法,研究了文献计量学在中国的发展情况。在进行大量文献研究和引文分析的基础上,介绍了一批文献计量学研究与应用的核心论文、核心著者与核心期刊  相似文献   

Schwerpunkt: Bildungsökonomie     

Norbert Neumann 《Zeitschrift für Erziehungswissenschaft》2008,11(2):165-167

  相似文献   

Harmonic analysis and the quantum theory     

Norbert Wiener 《Journal of The Franklin Institute》1929,207(4):525-534

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黎难秋  黎晓 《图书情报工作》1997,41(8):27-29,43

提出隐性目集的概念，并通过列举某些检索系统中的隐性条目集，探讨如何利用它们进行综合型检索，提高检索效率或进行特殊的检索，最后探讨自综合型检索的方法  相似文献   

Childhood Adversity and Self-Care Education for Undergraduate Social Work and Human Services Students     

Michelle Newcomb  Judith Burton  Niki Edwards 《Journal of Teaching in Social Work》2017,37(4):337-352

Many students pursuing social work and human services courses have experienced adverse childhoods. This article focuses on their learning about self-care, an important skill for future practice. Interviews with 20 undergraduate students with a history of childhood adversity found unmet needs both for conceptualizing self-care and developing strategies to implement self-care in their day-to-day lives. Many cited limited role modeling and little importance placed on self-care during childhood. Teaching self-care is conceptualized as not only a core skill for practice but also an equity issue for students with a history of childhood adversity.  相似文献   

Sandra K. Abell and Norman G. Lederman (eds): Handbook of Research in Science Education     

Mar��a Pilar Jim��nez-Aleixandre 《Science & Education》2011,20(5-6):577-583

  相似文献   

An indigenous and migrant critique of principles and innovation in education in Aotearoa/New Zealand     

Mere K��pa  Linit�� Manu��atu 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2011,57(5-6):617-630

This paper questions notions of individualism underpinning technocratic approaches to education that marginalise indigenous and migrant peoples?? knowledges in tertiary education. Focusing on New Zealand (Aotearoa) with its colonial and immigrant history, its M??ori and Pacific Islander citizens, the authors ask whether education, as its process is being communicated there, leaves indigenous and migrant people vulnerable and marginalised in the dominant, English-speaking, New Zealand European (P??keh??) mainstream society. The question is whether education refers to capacity-building and strengthening the potential of marginalised students?? language and culture; or whether it is only geared towards sustaining English-language ascendancy and technical virtuosity. Taking on board the cultural heritage of Pacific Islanders (Pasifika) resident in New Zealand, a new teacher training diploma was introduced by the Auckland University of Technology in 2004. Both authors are involved in the panel meetings (Fono) where the papers presented during the diploma course are evaluated.  相似文献   

A first-language-first multilingual model to meet the quality imperative in formal basic education in three ‘francophone’ West African countries     

Norbert Nikièma 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2011,38(2):599-616

This paper documents the new trend towards a first-language-first multilingual model in formal education in three former French colonies of West Africa, namely Burkina Faso, Mali and Niger. It compares the sociolinguistic situations, the conditions of the development of multilingual education and the achievements of mother-tongue-medium education in all three countries. The evidence is that, contrary to common discourse in francophonie, a strong first-language-first model in formal education is the best guarantee of a good mastery of French and, more generally, of quality education in francophone countries.  相似文献