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MacFarlane, A.; Robertson, S.E.; McCann, J.A.: Parallel computing for passage retrieval (2004) 0.03

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Abstract: In this paper methods for both speeding up passage processing and examining more passages using parallel computers are explored. The number of passages processed are varied in order to examine the effect on retrieval effectiveness and efficiency. The particular algorithm applied has previously been used to good effect in Okapi experiments at TREC. This algorithm and the mechanism for applying parallel computing to speed up processing are described.
Date: 20. 1.2007 18:30:22

Robertson, S.E.: ¬The methodology of information retrieval experiment (1981) 0.01

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Source: Information retrieval experiment. Ed.: K. Sparck Jones

Robertson, S.E.: Indexing theory and retrieval effectiveness (1979) 0.01

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Robertson, S.E.; Beaulieu, M.: Research and evaluation in information retrieval (1997) 0.01

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Abstract: Offered as a discussion document drawing on the experiences of the Okapi team in developing information retrieval systems. Raises some of the issues currently exercising the information retrieval community in the context of experimentation and evaluation
Footnote: Contribution to a thematic issue on Okapi and information retrieval research

MacFarlane, A.; Robertson, S.E.; McCann, J.A.: Parallel computing in information retrieval : an updated review (1997) 0.01

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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

Robertson, S.E.; Walker, S.: Some simple effective approximations to the 2-Poisson molde for probabilisitc weighted retrieval (1979) 0.01

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Footnote: Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.345-453.

Robertson, S.E.; Walker, S.; Beaulieu, M.: Laboratory experiments with Okapi : participation in the TREC programme (1997) 0.01
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Abstract

Briefly reviews the history of laboratory testing of information retrieval systems, focusing on the idea of a general purpose test collection of documents, queries and relevance judgements. Gives an overview of the methods used in TREC (Text Retrieval Conference) which is concerned with an ideal test collection, and discusses the Okapi team's participation in TREC. Also discusses some of the issues surrounding the difficult problem of interactive evaluation in TREC. The reconciliation of the requirements of the laboratory context with the concerns of interactive retrieval has a long way to go

Footnote

Contribution to a thematic issue on Okapi and information retrieval research

Robertson, S.E.: Theories and models in information retrieval (1977) 0.01

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Abstract: This paper is concerned with recent work in the theory of information retrieval. More particularly, it is concerned with theories which tackle the problem of retrieval performance, in a sense which will be explained. The aim is not an exhaustive survey of such work; rather it is an analysis and synthesis of those contributions which I feel to be important or find interesting

Huang, X.; Robertson, S.E.: Application of probilistic methods to Chinese text retrieval (1997) 0.01
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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

Robertson, S.E.: Some recent theories and models in information retrieval (1980) 0.01

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Sparck Jones, K.; Walker, S.; Robertson, S.E.: ¬A probabilistic model of information retrieval : development and comparative experiments - part 1 (2000) 0.01

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Sparck Jones, K.; Walker, S.; Robertson, S.E.: ¬A probabilistic model of information retrieval : development and comparative experiments - part 2 (2000) 0.01

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Robertson, S.E.; Walker, S.; Beaulieu, M.M.; Gatford, M.; Payne, A.: Okapi at TREC-4 (1996) 0.01

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Source: The Fourth Text Retrieval Conference (TREC-4). Ed.: K. Harman

Robertson, S.E.: ¬The probability ranking principle in IR (1977) 0.01

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Footnote: Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willet. San Francisco: Morgan Kaufmann 1997. S.281-286.

Beaulieu, M.M.; Gatford, M.; Huang, X.; Robertson, S.E.; Walker, S.; Williams, P.: Okapi an TREC-5 (1997) 0.01

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Source: The Fifth Text Retrieval Conference (TREC-5). Ed.: E.M. Voorhees u. D.K. Harman

Robertson, S.E.: On term selection for query expansion (1990) 0.01

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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
Theme: Semantisches Umfeld in Indexierung u. Retrieval

Robertson, S.E.: Overview of the Okapi projects (1997) 0.01

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Abstract: Gives a brief description of the Okapi projects and of the work of the centre for Interactive Systems Research in the Department of Information Science at City University, London,UK, where these projects have been developed. Describes firstly one version of an information retrieval system which contains some of the central features of the Okapi projects, and follows this with an indication of the variety of systems now implemented or implementable within the present setup
Footnote: Contribution to a thematic issue on Okapi and information retrieval research

Robertson, S.E.: On relevance weight estimation and query expansion (1986) 0.01

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Theme: Semantisches Umfeld in Indexierung u. Retrieval

Robertson, S.E.: ¬The parametric description of retrieval tests : Part II: Overall measures (1969) 0.01
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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.
MacFarlane, A.; McCann, J.A.; Robertson, S.E.: Parallel methods for the generation of partitioned inverted files (2005) 0.00
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Abstract

Purpose - The generation of inverted indexes is one of the most computationally intensive activities for information retrieval systems: indexing large multi-gigabyte text databases can take many hours or even days to complete. We examine the generation of partitioned inverted files in order to speed up the process of indexing. Two types of index partitions are investigated: TermId and DocId. Design/methodology/approach - We use standard measures used in parallel computing such as speedup and efficiency to examine the computing results and also the space costs of our trial indexing experiments. Findings - The results from runs on both partitioning methods are compared and contrasted, concluding that DocId is the more efficient method. Practical implications - The practical implications are that the DocId partitioning method would in most circumstances be used for distributing inverted file data in a parallel computer, particularly if indexing speed is the primary consideration. Originality/value - The paper is of value to database administrators who manage large-scale text collections, and who need to use parallel computing to implement their text retrieval services.

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