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  • × author_ss:"Robertson, S.E."
  1. MacFarlane, A.; Robertson, S.E.; McCann, J.A.: Parallel computing for passage retrieval (2004) 0.03
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    Date
    20. 1.2007 18:30:22
    Type
    a
  2. Robertson, S.E.: Indexing theory and retrieval effectiveness (1979) 0.00
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    Type
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  3. Bovey, J.D.; Robertson, S.E.: ¬An algorithm for weighted searching on a Boolean system (1984) 0.00
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    Type
    a
  4. Robertson, S.E.: On term selection for query expansion (1990) 0.00
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    Abstract
    In the framework of a relevance feedback system, term values or term weights may be used to (a) select new terms for inclusion in a query, and/or (b) weight the terms for retrieval purposes once selected. It has sometimes been assumed that the same weighting formula should be used for both purposes. This paper sketches a quantitative argument which suggests that the two purposes require different weighting formulae
    Type
    a
  5. Robertson, S.E.: Query-document symmetry and dual models (1994) 0.00
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    Abstract
    The idea that there is some natural symmetry between queries and documents is explained. If symmetry can be assumed, then it lead to a conception of 'dual' models in information retrieval (given a model, we can construct a dual model in which the roles of documents and queries are reversed). But symmetry breaks down in various ways, which may invalidate this construction. If we can construct a dual, it is not obvious that it can be combined with the original
    Type
    a
  6. Robertson, S.E.: ¬The parametric description of retrieval tests : Part I: The basic parameters (1969) 0.00
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    Abstract
    Some parameters and techniques in use for describing the results of test on IR system are analysed. Several considerations outside the scope of the usual 2X2 table are relevant to the choice of parameters. In particular, a variable which produces a 'performance curve' of a system corresponds to an extension of the 2x2 table. Also, the statistical relationships between parameters are all-important. It is considered that precision is not such a useful measure of performance (in conjunction with recall)as fallout. A more powerful alternative to Cleverdon's 'invitable inverse relationship between recall and precision'is proposed and justified, namely that the recall-fallout graph is convex.
    Type
    a
  7. Sparck Jones, K.; Walker, S.; Robertson, S.E.: ¬A probabilistic model of information retrieval : development and comparative experiments - part 1 (2000) 0.00
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    Type
    a
  8. Sparck Jones, K.; Walker, S.; Robertson, S.E.: ¬A probabilistic model of information retrieval : development and comparative experiments - part 2 (2000) 0.00
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    Type
    a
  9. Robertson, S.E.; Walker, S.; Beaulieu, M.: Experimentation as a way of life : Okapi at TREC (2000) 0.00
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    Type
    a
  10. Robertson, S.E.; Walker, S.; Beaulieu, M.M.; Gatford, M.; Payne, A.: Okapi at TREC-4 (1996) 0.00
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    Type
    a
  11. Robertson, S.E.; Belkin, N.J.: Ranking in principle (1978) 0.00
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    Type
    a
  12. Robertson, S.E.; Hancock-Beaulieu, M.M.: On the evaluation of IR systems (1992) 0.00
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    Type
    a
  13. Robertson, S.E.: ¬The probabilistic character of relevance (1977) 0.00
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    Type
    a
  14. Robertson, S.E.; Sparck Jones, K.: Relevance weighting of search terms (1976) 0.00
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    Abstract
    Examines statistical techniques for exploiting relevance information to weight search terms. These techniques are presented as a natural extension of weighting methods using information about the distribution of index terms in documents in general. A series of relevance weighting functions is derived and is justified by theoretical considerations. In particular, it is shown that specific weighted search methods are implied by a general probabilistic theory of retrieval. Different applications of relevance weighting are illustrated by experimental results for test collections
    Type
    a
  15. Robertson, S.E.: ¬The methodology of information retrieval experiment (1981) 0.00
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  16. MacFarlane, A.; Robertson, S.E.; McCann, J.A.: Parallel computing in information retrieval : an updated review (1997) 0.00
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    Abstract
    Reviews the progress of parallel computing in information retrieval. Stresses the importance of the motivation is using parallel computing for text retrieval. Analyzes parallel IR systems using a classification defined by Rasmussen and describes some parallel IR systems. Gives a description of the retrieval models used in parallel information processing and notes areas where research is needed
    Type
    a
  17. Robertson, S.E.: ¬The parametric description of retrieval tests : Part II: Overall measures (1969) 0.00
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    Abstract
    Two general requirements for overall measures of retrieval effectiveness are proposed, namely that the measures should be as far as possible independent of generality (this is interpreted to mean that it can be described in terms of recall and fallout), and that it should be able to measure the effectiveness of a performance curve (it should not be restricted to a simple 2X2 table). Several measures that have been proposed are examined with these conditions in mind. It turns out that most of the satisfactory ones are directly or indirectly related to swet's measure A, the area under the recall-fallout curve. In particular, Brookes' measure S and Rocchio's normalized recall are versions of A.
    Type
    a
  18. Huang, X.; Robertson, S.E.: Application of probilistic methods to Chinese text retrieval (1997) 0.00
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    Abstract
    Discusses the use of text retrieval methods based on the probabilistic model with Chinese language material. Since Chinese text has no natural word boundaries, either a dictionary based word segmentation method must be applied to the text, or indexing and searching must be done in terms of single Chinese characters. In either case, it becomes important to have a good way of dealing with phrases or contoguous strings of characters; the probabilistic model does not at present have such a facility. Proposes some ad hoc modifications of the probabilistic weighting function and matching method for this purpose
    Footnote
    Contribution to a thematic issue on Okapi and information retrieval research
    Type
    a
  19. Vechtomova, O.; Karamuftuoglum, M.; Robertson, S.E.: On document relevance and lexical cohesion between query terms (2006) 0.00
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    Abstract
    Lexical cohesion is a property of text, achieved through lexical-semantic relations between words in text. Most information retrieval systems make use of lexical relations in text only to a limited extent. In this paper we empirically investigate whether the degree of lexical cohesion between the contexts of query terms' occurrences in a document is related to its relevance to the query. Lexical cohesion between distinct query terms in a document is estimated on the basis of the lexical-semantic relations (repetition, synonymy, hyponymy and sibling) that exist between there collocates - words that co-occur with them in the same windows of text. Experiments suggest significant differences between the lexical cohesion in relevant and non-relevant document sets exist. A document ranking method based on lexical cohesion shows some performance improvements.
    Type
    a
  20. Vechtomova, O.; Robertson, S.E.: ¬A domain-independent approach to finding related entities (2012) 0.00
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    Abstract
    We propose an approach to the retrieval of entities that have a specific relationship with the entity given in a query. Our research goal is to investigate whether related entity finding problem can be addressed by combining a measure of relatedness of candidate answer entities to the query, and likelihood that the candidate answer entity belongs to the target entity category specified in the query. An initial list of candidate entities, extracted from top ranked documents retrieved for the query, is refined using a number of statistical and linguistic methods. The proposed method extracts the category of the target entity from the query, identifies instances of this category as seed entities, and computes similarity between candidate and seed entities. The evaluation was conducted on the Related Entity Finding task of the Entity Track of TREC 2010, as well as the QA list questions from TREC 2005 and 2006. Evaluation results demonstrate that the proposed methods are effective in finding related entities.
    Type
    a