Search (27 results, page 1 of 2)

  • × author_ss:"Willett, P."
  1. Wade, S.J.; Willett, P.; Bawden, D.: SIBRIS : the Sandwich Interactive Browsing and Ranking Information System (1989) 0.01 
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    Abstract
    SIBRIS (Sandwich Interactive Browsing and Ranking Information System) is an interactive text retrieval system which has been developed to support the browsing of library and product files at Pfizer Central Research, Sandwich, UK. Once an initial ranking has been produced, the system will allow the user to select any document displayed on the screen at any point during the browse and to use that as the basis for another search. Facilities have been included to enable the user to keep track of the browse and to facilitate backtracking, thus allowing the user to move away from the original query to wander in and out of different areas of interest.
    Source
    Journal of information science. 15(1989) no.4/5, S.249-260
  2. Robertson, M.; Willett, P.: ¬An upperbound to the performance of ranked output searching : optimal weighting of query terms using a genetic algorithms (1996) 0.01 
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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
  3. Furner, J.; Willett, P.: ¬A survey of hypertext-based public-access point-of-information systems in UK libraries (1995) 0.01 
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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
    Source
    Journal of information science. 21(1995) no.4, S.243-255
  4. Clarke, S.J.; Willett, P.: Estimating the recall performance of Web search engines (1997) 0.01 
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    Abstract
    Reports a comparison of the retrieval effectiveness of the AltaVista, Excite and Lycos Web search engines. Describes a method for comparing the recall of the 3 sets of searches, despite the fact that they are carried out on non identical sets of Web pages. It is thus possible, unlike previous comparative studies of Web search engines, to consider both recall and precision when evaluating the effectiveness of search engines
  5. Al-Hawamdeh, S.; Smith, G.; Willett, P.: Paragraph-based access to full-text documents using a hypertext system (1991) 0.01 
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  6. Furner-Hines, J.; Willett, P.: ¬The use of hypertext in libraries in the United Kingdom (1994) 0.00 
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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
  7. Ellis, D.; Furner-Hines, J.; Willett, P.: On the creation of hypertext links in full-text documents : measurement of inter-linker consistency (1994) 0.00 
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    Abstract
    In important stage in the process of retrieval of objects from a hypertext database is the creation of a set of inter-nodal links that are intended to represent the relationships existing between objects; this operation is often undertaken manually, just as index terms are often manually assigned to documents in a conventional retrieval system. Studies of conventional systems have suggested that a degree of consistency in the terms assigned to documents by indexers is positively associated with retrieval effectiveness. It is thus of interest to investigate the consistency of assignment of links in separate hypertext versions of the same full-text document, since a measure of agreement may be related to the subsequent utility of the resulting hypertext databases. The calculation of values indicating the degree of similarity between objects is a technique that has been widely used in the fields of textual and chemical information retrieval; in this paper we describe the application of arithmetic coefficients and topological indices to the measurement of the degree of similarity between the sets of inter-nodal links in hypertext databases. We publish the results of a study in which several different of links are inserted, by different people, between the paragraphs of each of a number of full-text documents. Our results show little similary between the sets of links identified by different people; this finding is comparable with those of studies of inter-indexer consistency, where it has been found that there is generally only a low level of agreement between the sets of idenx terms assigned to a document by different indexers
  8. Ellis, D.; Furner, J.; Willett, P.: On the creation of hypertext links in full-text documents : measurement of retrieval effectiveness (1996) 0.00 
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    Abstract
    An important stage in the process or retrieval of objects from a hypertext database is the creation of a set of internodal links that are intended to represent the relationships existing between objects; this operation is often undertaken manually, just as index terms are often manually assigned to documents in a conventional retrieval system. In an earlier article (1994), the results were published of a study in which several different sets of links were inserted, each by a different person, between the paragraphs of each of a number of full-text documents. These results showed little similarity between the link-sets, a finding that was comparable with those of studies of inter-indexer consistency, which suggest that there is generally only a low level of agreement between the sets of index terms assigned to a document by different indexers. In this article, a description is provided of an investigation into the nature of the relationship existing between (i) the levels of inter-linker consistency obtaining among the group of hypertext databases used in our earlier experiments, and (ii) the levels of effectiveness of a number of searches carried out in those databases. An account is given of the implementation of the searches and of the methods used in the calculation of numerical values expressing their effectiveness. Analysis of the results of a comparison between recorded levels of consistency and those of effectiveness does not allow us to draw conclusions about the consistency - effectiveness relationship that are equivalent to those drawn in comparable studies of inter-indexer consistency
    Source
    Journal of the American Society for Information Science. 47(1996) no.4, S.287-300
  9. Artymiuk, P.J.; Spriggs, R.V.; Willett, P.: Graph theoretic methods for the analysis of structural relationships in biological macromolecules (2005) 0.00 
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    Date
    22. 7.2006 14:40:10
    Source
    Journal of the American Society for Information Science and Technology. 56(2005) no.5, S.518-528
  10. Furner-Hines, J.; Willett, P.: ¬The use of hypertext in libraries in the United Kingdom (1994) 0.00 
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    Abstract
    Presents a summary of the major findings of a survey of the use of hypertext systems and the production of hypertext products in UK libraries. Not surprisingly, academic libraries are found to be both the most enthusiastic users and producers. There are normally 4 principal stages in a library's development of a hypertext system, although the possibility of leapfrogging via WWW is acknowledged
  11. Griffiths, A.; Luckhurst, H.C.; Willett, P.: Using interdocument similarity information in document retrieval systems (1986) 0.00 
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    Source
    Journal of the American Society for Information Science. 37(1986) no.1, S.3-11
  12. Perry, R.; Willett, P.: ¬A revies of the use of inverted files for best match searching in information retrieval systems (1983) 0.00 
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    Source
    Journal of information science. 6(1983), S.59-66
  13. Li, J.; Willett, P.: ArticleRank : a PageRank-based alternative to numbers of citations for analysing citation networks (2009) 0.00 
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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.
  14. Wakeling, S.; Spezi, V.; Fry, J.; Creaser, C.; Pinfield, S.; Willett, P.: Academic communities : the role of journals and open-access mega-journals in scholarly communication (2019) 0.00 
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    Abstract
    Purpose The purpose of this paper is to provide insights into publication practices from the perspective of academics working within four disciplinary communities: biosciences, astronomy/physics, education and history. The paper explores the ways in which these multiple overlapping communities intersect with the journal landscape and the implications for the adoption and use of new players in the scholarly communication system, particularly open-access mega-journals (OAMJs). OAMJs (e.g. PLOS ONE and Scientific Reports) are large, broad scope, open-access journals that base editorial decisions solely on the technical/scientific soundness of the article. Design/methodology/approach Focus groups with active researchers in these fields were held in five UK Higher Education Institutions across Great Britain, and were complemented by interviews with pro-vice-chancellors for research at each institution. Findings A strong finding to emerge from the data is the notion of researchers belonging to multiple overlapping communities, with some inherent tensions in meeting the requirements for these different audiences. Researcher perceptions of evaluation mechanisms were found to play a major role in attitudes towards OAMJs, and interviews with the pro-vice-chancellors for research indicate that there is a difference between researchers' perceptions and the values embedded in institutional frameworks. Originality/value This is the first purely qualitative study relating to researcher perspectives on OAMJs. The findings of the paper will be of interest to publishers, policy-makers, research managers and academics.
  15. Willett, P.: Recent trends in hierarchic document clustering : a critical review (1988) 0.00 
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    Source
    Information processing and management. 24(1988) no.5, S.577-597
  16. Ingwersen, P.; Willett, P.: ¬An introduction to algorithmic and cognitive approaches for information retrieval (1995) 0.00 
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    Abstract
    This paper provides an over-view of 2, complementary approaches to the design and implementation of information retrieval systems. The first approach focuses on the algorithms and data structures that are needed to maximise the effectiveness and the efficiency of the searches that can be carried out on text databases, while the second adopts a cognitive approach that focuses on the role of the user and of the knowledge sources involved in information retrieval. The paper argues for an holistic view of information retrieval that is capable of encompassing both of these approaches
  17. Robertson, A.M.; Willett, P.: Use of genetic algorithms in information retrieval (1995) 0.00 
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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
  18. Robertson, A.M.; Willett, P.: Applications of n-grams in textual information systems (1998) 0.00 
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    Abstract
    Provides an introduction to the use of n-grams in textual information systems, where an n-gram is a string of n, usually adjacent, characters, extracted from a section of continuous text. Applications that can be implemented efficiently and effectively using sets of n-grams include spelling errors detection and correction, query expansion, information retrieval with serial, inverted and signature files, dictionary look up, text compression, and language identification
  19. Robertson, A.M.; Willett, P.: Retrieval techniques for historical English text : searching the sixteenth and seventeenth century titles in the Catalogue of Caterbury Cathedral Library using spelling-correction methods (1992) 0.00 
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    Imprint
    Oxford : Learned Information Ltd.
    Source
    Online information 92. Proc. of the 16th Int. Online Information Meeting, London, 8-10.12.1992. Ed. by David I. Raitt
  20. Jones, G.; Robertson, A.M.; Willett, P.: ¬An introduction to genetic algorithms and to their use in information retrieval (1994) 0.00 
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    Abstract
    This paper provides an introduction to genetic algorithms, a new approach to the investigation of computationally-intensive problems that may be insoluble using conventional, deterministic approaches. A genetic algorithm takes an initial set of possible starting solutions and then iteratively improves theses solutions using operators that are analogous to those involved in Darwinian evolution. The approach is illusrated by reference to several problems in information retrieval

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  • a 25
  • r 2

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