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  • × author_ss:"Willett, P."
  1. Jones, G.; Robertson, A.M.; Willett, P.: ¬An introduction to genetic algorithms and to their use in information retrieval (1994) 0.02 
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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
  2. Robertson, A.M.; Willett, P.: Generation of equifrequent groups of words using a genetic algorithm (1994) 0.01 
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    Abstract
    Genetic algorithms are a class of non-deterministic algorithms that derive from Darwinian evolution and that provide good, though not necessarily optimal, solutions to combinatorial problems. We describe their application to the identification of characteristics that occur approximately equifrequently in a database, using two different methods for the creation of the chromosome data structures that lie at the heart of a genetic algortihm. Experiments with files of English and Turkish text suggest that the genetic algorithm developed here can produce results superior to those produced by existing non-deterministic algorithms; however, the results are inferior to those produced by an existing deterministic algorithm
  3. Ellis, D.; Furner-Hines, J.; Willett, P.: Measuring the consistency of assignment of hypertext links in full-text documents (1994) 0.01 
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    Abstract
    Studies of document retrieval systems have suggested that the degree of consistency in the terms assigned to documents by indexers is positively associated with retrieval effectiveness. The study investigated the consistency of assignment of links in separate hypertext versions of the same full text database assuming that a measure of agreement may be related to the subsequent utility of the resulting hypertext document. Describes the calculations involved in measuring the degree of similarity between pairs of structured objetcs of a certain type (Those that may be represented in graph theoretic form). Initial results show little similarity between the sets of links identified by different people and this finding is comparable with those of studies of inter indexer consistency, where it has been found that there is generally only alow level of agreement between the sets of indexing terms assigned to a document of different indexers
  4. Ellis, D.; Furner-Hines, J.; Willett, P.: ¬The creation of hypertext links in full-text documents (1994) 0.01 
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    Abstract
    An important stage in the process of 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 objetcs; an operation that is usually undertaken manually such as the allocation of subject index terms to documents. Reports results of a study in which several different sets of hypertext links were inserted, each by a different person, between the paragraphs of each of a number of full text documents. The similarity between the members of each pair of link sets was then evaluated. Results indicated that little similarity existed among the link sets, a finding comparable with those of studies of inter indexer consistency, which suggests that there is generally only a low level of agreemenet between the sets of index terms assigned to a document by indexers. Concludes with that part of the study designed to test the validity of making these kinds of assumptions in the context of hypertext link sets
  5. Ellis, D.; Furner-Hines, J.; Willett, P.: On the creation of hypertext links in full-text documents : measurement of inter-linker consistency (1994) 0.01 
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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
  6. Ellis, D.; Furner, J.; Willett, P.: On the creation of hypertext links in full-text documents : measurement of retrieval effectiveness (1996) 0.01 
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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
  7. Li, J.; Willett, P.: ArticleRank : a PageRank-based alternative to numbers of citations for analysing citation networks (2009) 0.01 
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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.
  8. Artymiuk, P.J.; Spriggs, R.V.; Willett, P.: Graph theoretic methods for the analysis of structural relationships in biological macromolecules (2005) 0.01 
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    Date
    22. 7.2006 14:40:10

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