Search (22 results, page 1 of 2)

  • × author_ss:"Willett, P."
  1. Griffiths, A.; Luckhurst, H.C.; Willett, P.: Using interdocument similarity information in document retrieval systems (1986) 0.01 
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    Source
    Journal of the American Society for Information Science. 37(1986) no.1, S.3-11
  2. Perry, R.; Willett, P.: ¬A revies of the use of inverted files for best match searching in information retrieval systems (1983) 0.01 
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    Source
    Journal of information science. 6(1983), S.59-66
  3. 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
  4. 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
  5. 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
  6. 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
  7. Furner, J.; Willett, P.: ¬A survey of hypertext-based public-access point-of-information systems in UK libraries (1995) 0.00 
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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
  8. 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
  9. Wade, S.J.; Willett, P.; Bawden, D.: SIBRIS : the Sandwich Interactive Browsing and Ranking Information System (1989) 0.00 
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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
  10. 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
  11. Willett, P.: From chemical documentation to chemoinformatics : 50 years of chemical information science (2009) 0.00 
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    Source
    Information science in transition, Ed.: A. Gilchrist
  12. Willett, P.: Best-match text retrieval (1993) 0.00 
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    Source
    Library and information briefings. 1993, no.49, S.1-11
  13. Ellis, D.; Furner-Hines, J.; Willett, P.: Measuring the degree of similarity between objects in text retrieval systems (1993) 0.00 
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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
    Source
    Perspectives in information management. 3(1993) no.2, S.128-149
  14. Ellis, D.; Furner-Hines, J.; Willett, P.: Measuring the consistency of assignment of hypertext links in full-text documents (1994) 0.00 
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    Source
    Information retrieval: new systems and current research. Proceedings of the 15th Research Colloquium of the British Computer Society Information Retrieval Specialist Group, Glasgow 1993. Ed.: Ruben Leon
  15. Shaw, R.J.; Willett, P.: On the non-random nature of nearest-neighbour document clusters (1993) 0.00 
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    Source
    Information processing and management. 29(1993) no.4, S.449-452
  16. Robertson, M.; Willett, P.: ¬An upperbound to the performance of ranked output searching : optimal weighting of query terms using a genetic algorithms (1996) 0.00 
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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
  17. Ekmekcioglu, F.C.; Robertson, A.M.; Willett, P.: Effectiveness of query expansion in ranked-output document retrieval systems (1992) 0.00 
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    Source
    Journal of information science. 18(1992) no.2, S.139-147
  18. 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
  19. 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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    Source
    Journal of the American Society for Information Science and Technology. 56(2005) no.5, S.518-528
  20. 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

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