Search (12 results, page 1 of 1)

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Abstract

Reviews the basic techniques involving genetic algorithms and their application to 2 problems in information retrieval: the generation of equifrequent groups of index terms; and the identification of optimal query and term weights. The algorithm developed for the generation of equifrequent groupings proved to be effective in operation, achieving results comparable with those obtained using a good deterministic algorithm. The algorithm developed for the identification of optimal query and term weighting involves fitness function that is based on full relevance information

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Abstract

Reports an evaluation of 3 methods for the expansion of natural language queries in ranked output retrieval systems. The methods are based on term co-occurrence data, on Soundex codes, and on a string similarity measure. Searches for 110 queries in a data base of 26.280 titles and abstracts suggest that there is no significant difference in retrieval effectiveness between any of these methods and unexpanded searches

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Abstract

Provides an introduction to the computational techniques that underlie best match searching retrieval systems. Discusses: problems of traditional Boolean systems; characteristics of best-match searching; automatic indexing; term conflation; matching of documents and queries (dealing with similarity measures, initial weights, relevance weights, and the matching algorithm); and describes operational best-match systems

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Abstract

Describes the use of a variety of similarity coefficients in the measurement of the degree of similarity between objects that contain textual information, such as documents, paragraphs, index terms or queries. The work is intended as a preliminary to future investigation of the calculations involved in measuring the degree of similarity between structured objects that may be represented by graph theoretic forms. Descusses the role of similarity coefficients in text retrieval in terms of: document and query similarity; document and document similarity; cocitation analysis; term and term similarity; and the similarity between sets of judgements, such as relevance judgements. Describes several methods for expressing the formulae used to define similarity coefficients and compares their attributes. Concludes with details the characteristics of similarity coefficients; equivalence and monotonicity; consideration of negative matches; geometric analyses; and the meaning of correlation coefficients

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Date

22. 7.2006 14:40:10

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Abstract

Purpose - The purpose of this paper is to suggest an alternative to the widely used Times Cited criterion for analysing citation networks. The approach involves taking account of the natures of the papers that cite a given paper, so as to differentiate between papers that attract the same number of citations. Design/methodology/approach - ArticleRank is an algorithm that has been derived from Google's PageRank algorithm to measure the influence of journal articles. ArticleRank is applied to two datasets - a citation network based on an early paper on webometrics, and a self-citation network based on the 19 most cited papers in the Journal of Documentation - using citation data taken from the Web of Knowledge database. Findings - ArticleRank values provide a different ranking of a set of papers from that provided by the corresponding Times Cited values, and overcomes the inability of the latter to differentiate between papers with the same numbers of citations. The difference in rankings between Times Cited and ArticleRank is greatest for the most heavily cited articles in a dataset. Originality/value - This is a novel application of the PageRank algorithm.

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Abstract

We have recently completed a survey of the operational use of hypertext-based information systems in academic, public and special libraries in the UK. A literatur search, questionnaire and both telephone and face-to-face interviews demonstrate that the principle application of hypertext systems is for the implementation of public-access point-of-information systems, which provide guidance to the users of local information resources. In this paper, we describe the principle issuse relating to the design and usage of these systems that were raised in the interviews and that we experienced when using the systems for ourselves. We then present a set of technical recommendations with the intention of helping the developers of future systems, with special attention being given to the need to develop effective methods for system evaluation

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Abstract

Describes the development of a genetic algorithm (GA) for the assignment of weights to query terms in a ranked output document retrieval system. The GA involves a fitness function that is based on full relevance information, and the rankings resulting from the use of these weights are compared with the Robertson-Sparck Jones F4 retrospective relevance weight

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Abstract

Purpose The purpose of this paper is to develop a content analysis framework and from that derive a process model of knowledge construction in the context of virtual product user communities, organization sponsored online forums where product users collaboratively construct knowledge to solve their technical problems. Design/methodology/approach The study is based on a deductive and qualitative content analysis of discussion threads about solving technical problems selected from a series of virtual product user communities. Data are complemented with thematic analysis of interviews with forum members. Findings The research develops a content analysis framework for knowledge construction. It is based on a combination of existing codes derived from frameworks developed for computer-supported collaborative learning and new categories identified from the data. Analysis using this framework allows the authors to propose a knowledge construction process model showing how these elements are organized around a typical "trial and error" knowledge construction strategy. Practical implications The research makes suggestions about organizations' management of knowledge activities in virtual product user communities, including moderators' roles in facilitation. Originality/value The paper outlines a new framework for analysing knowledge activities where there is a low level of critical thinking and a model of knowledge construction by trial and error. The new framework and model can be applied in other similar contexts.

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Abstract

State of the art review of hypertext systems in use in UK libraries. Systems include public access point of information (POI) systems that provide guidance to users of local resources, and networked document retrieval systems, such as WWW, that enable users to access texts stored on machines linked by the Internet. Particular emphasis is placed on those systems that are produced inhouse by the libraries in which they are used. The review is based on a series of telephone or face to face interviews conducted with representatives of those organizations that a literature review and mailed questionnaire survey identified as current users of hypertext. Considers issues relating to system development and usability, and presents a set of appropriate guidelines for the designers of future systems. Concludes that: the principle application of hypertext systems in UK libraries is in the implementation of POI systems; that such development is most advanced in the academic sector; and that such development is set to increase in tandem with use of the WWW

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Abstract

Purpose Open-access mega-journals (OAMJs) represent an increasingly important part of the scholarly communication landscape. OAMJs, such as PLOS ONE, are large scale, broad scope journals that operate an open access business model (normally based on article-processing charges), and which employ a novel form of peer review, focussing on scientific "soundness" and eschewing judgement of novelty or importance. The purpose of this paper is to examine the discourses relating to OAMJs, and their place within scholarly publishing, and considers attitudes towards mega-journals within the academic community. Design/methodology/approach This paper presents a review of the literature of OAMJs structured around four defining characteristics: scale, disciplinary scope, peer review policy, and economic model. The existing scholarly literature was augmented by searches of more informal outputs, such as blogs and e-mail discussion lists, to capture the debate in its entirety. Findings While the academic literature relating specifically to OAMJs is relatively sparse, discussion in other fora is detailed and animated, with debates ranging from the sustainability and ethics of the mega-journal model, to the impact of soundness-only peer review on article quality and discoverability, and the potential for OAMJs to represent a paradigm-shifting development in scholarly publishing. Originality/value This paper represents the first comprehensive review of the mega-journal phenomenon, drawing not only on the published academic literature, but also grey, professional and informal sources. The paper advances a number of ways in which the role of OAMJs in the scholarly communication environment can be conceptualised.