Literatur zur Informationserschließung

Diese Datenbank enthält über 40.000 Dokumente zu Themen aus den Bereichen Formalerschließung – Inhaltserschließung – Information Retrieval.

© 2015 W. Gödert, TH Köln, Institut für Informationswissenschaft / Powered by litecat, BIS Oldenburg (Stand: 28. April 2022)

Suchergebnisse

• 1
  Lu, W. ; MacFarlane, A. ; Venuti, F.: Okapi-based XML indexing.
  In: Aslib proceedings. 61(2009) no.5, S.483-499.
  
  Abstract: Purpose - Being an important data exchange and information storage standard, XML has generated a great deal of interest and particular attention has been paid to the issue of XML indexing. Clear use cases for structured search in XML have been established. However, most of the research in the area is either based on relational database systems or specialized semi-structured data management systems. This paper aims to propose a method for XML indexing based on the information retrieval (IR) system Okapi. Design/methodology/approach - First, the paper reviews the structure of inverted files and gives an overview of the issues of why this indexing mechanism cannot properly support XML retrieval, using the underlying data structures of Okapi as an example. Then the paper explores a revised method implemented on Okapi using path indexing structures. The paper evaluates these index structures through the metrics of indexing run time, path search run time and space costs using the INEX and Reuters RVC1 collections. Findings - Initial results on the INEX collections show that there is a substantial overhead in space costs for the method, but this increase does not affect run time adversely. Indexing results on differing sized Reuters RVC1 sub-collections show that the increase in space costs with increasing the size of a collection is significant, but in terms of run time the increase is linear. Path search results show sub-millisecond run times, demonstrating minimal overhead for XML search. Practical implications - Overall, the results show the method implemented to support XML search in a traditional IR system such as Okapi is viable. Originality/value - The paper provides useful information on a method for XML indexing based on the IR system Okapi.
  
  Objekt: Okapi ; XML
  
  
• 2
  Robertson, S.: How Okapi came to TREC.
  In: TREC: experiment and evaluation in information retrieval. Ed.: E.M. Voorhees, u. D.K. Harman. Cambridge, MA : MIT Press, 2005. S.287-300.
  
  Themenfeld: Retrievalstudien
  Objekt: TREC ; OKAPI
  
  
• 3
  MacFarlane, A. ; Robertson, S.E. ; McCann, J.A.: Parallel computing for passage retrieval.
  In: Aslib proceedings. 56(2004) no.4, S.201-211.
  
  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.
  
  Themenfeld: Retrievalalgorithmen
  Objekt: Okapi ; TREC
  
  
• 4
  Kang, I.-H. ; Kim, G.C.: Integration of multiple evidences based on a query type for web search.
  In: Information processing and management. 40(2004) no.3, S.459-478.
  
  Abstract: The massive and heterogeneous Web exacerbates IR problems and short user queries make them worse. The contents of web pages are not enough to find answer pages. PageRank compensates for the insufficiencies of content information. The content information and PageRank are combined to get better results. However, static combination of multiple evidences may lower the retrieval performance. We have to use different strategies to meet the need of a user. We can classify user queries as three categories according to users' intent, the topic relevance task, the homepage finding task, and the service finding task. In this paper, we present a user query classification method. The difference of distribution, mutual information, the usage rate as anchor texts and the POS information are used for the classification. After we classified a user query, we apply different algorithms and information for the better results. For the topic relevance task, we emphasize the content information, on the other hand, for the homepage finding task, we emphasize the Link information and the URL information. We could get the best performance when our proposed classification method with the OKAPI scoring algorithm was used.
  
  Themenfeld: Retrievalalgorithmen
  Objekt: Okapi
  
  
• 5
  Vakkari, P. ; Jones, S. ; MacFarlane, A. ; Sormunen, E.: Query exhaustivity, relevance feedback and search success in automatic and interactive query expansion.
  In: Journal of documentation. 60(2004) no.2, S.109-127.
  
  Abstract: This study explored how the expression of search facets and relevance feedback (RF) by users was related to search success in interactive and automatic query expansion in the course of the search process. Search success was measured both in the number of relevant documents retrieved, whether identified by users or not. Research design consisted of 26 users searching for four TREC topics in Okapi IR system, half of the searchers using interactive and half automatic query expansion based on RF. The search logs were recorded, and the users filled in questionnaires for each topic concerning various features of searching. The results showed that the exhaustivity of the query was the most significant predictor of search success. Interactive expansion led to better search success than automatic expansion if all retrieved relevant items were counted, but there was no difference between the methods if only those items recognised relevant by users were observed. The analysis showed that the difference was facilitated by the liberal relevance criterion used in TREC not favouring highly relevant documents in evaluation.
  
  Anmerkung: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/00220410410522016
  
  Themenfeld: Benutzerstudien
  Objekt: Okapi
  
  
• 6
  Beaulieu, M. ; Gatford, M. ; Jones, S.: Widening access to Okapi.
  London : British Library, 2000. 24,33 S.
  ISBN 1-902394-30-5
  (British Library: Library and Information Commission research report; 58)
  
  Themenfeld: OPAC
  Objekt: Okapi
  
  
• 7
  Robertson, S.E. ; Walker, S. ; Beaulieu, M.: Experimentation as a way of life : Okapi at TREC.
  In: Information processing and management. 36(2000) no.1, S.95-108.
  
  Themenfeld: OPAC ; Retrievalstudien
  Objekt: Okapi ; TREC
  
  
• 8
  Schulz, U.: "Wie der Schnabel gewachsen ist" : Über die Qualität von OPACs - Anforderungen, Realität, Perspektiven.
  In: BuB. 50(1998) H.5, S.345-351.
  
  Abstract: Ob Erwachsene oder Kinder die Bibliothek besuchen, Schwierigkeiten mit dem Handling von OPACs sind fast die Regel und gleichen sich überall auf der Welt. Durch Forschungen und Projekte ist seit langem bekannt, woraus diese Schwierigkeiten resultieren und wie ihnen abgeholfen werden könnte - bisher aber waren Bibliothekare auf diesem Gebiet keine guten Anwälte ihrer Kunden
  
  Themenfeld: OPAC
  Objekt: OKAPI ; BOOKHOUSE ; Bücherschatz ; Kid's catalog
  
  
• 9
  Lüke, S.: Retrievaleigenschaften von Online-Publikumskatalogen, dargestellt am Beispiel OKAPI.
  Köln : Fachhochschule, Fachbereich Bibliotheks- und Informationswesen, 1998. IV,36 S.
  
  Anmerkung: [Diplomarbeit zur Prüfung für den Studiengang öffentliches Bibliothekswesen]
  
  Themenfeld: OPAC
  Objekt: OKAPI
  
  
• 10
  Beaulieu, M. ; Jones, S.: Interactive searching and interface issues in the Okapi best match probabilistic retrieval system.
  In: Interacting with computers. 10(1998) no.3, S.237-248.
  
  Abstract: Explores interface design raised by the development and evaluation of Okapi, a highly interactive information retrieval system based on a probabilistic retrieval model with relevance feedback. It uses terms frequency weighting functions to display retrieved items in a best match ranked order; it can also find additional items similar to those marked as relevant by the searcher. Compares the effectiveness of automatic and interactive query expansion in different user interface environments. focuses on the nature of interaction in information retrieval and the interrelationship between functional visibility, the user's cognitive loading and the balance of control between user and system
  
  Themenfeld: OPAC ; Retrievalalgorithmen ; Semantisches Umfeld in Indexierung u. Retrieval ; Suchoberflächen
  Objekt: Okapi
  
  
• 11
  Robertson, S.E. ; Walker, S. ; Beaulieu, M.: Laboratory experiments with Okapi : participation in the TREC programme.
  In: Journal of documentation. 53(1997) no.1, S.20-34.
  
  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
  
  Inhalt: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/EUM0000000007188.
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research ;
  
  Themenfeld: Retrievalstudien
  Objekt: Okapi
  
  
• 12
  Robertson, S.E. ; Beaulieu, M.: Research and evaluation in information retrieval.
  In: Journal of documentation. 53(1997) no.1, S.51-57.
  
  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
  
  Inhalt: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/EUM0000000007190.
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research ;
  
  Objekt: Okapi
  
  
• 13
  Jones, S.: Transaction logging.
  In: Journal of documentation. 53(1997) no.1, S.35-50.
  
  Abstract: Discusses the use of transaction logging in Okapi related projects to allow search algorithms and user interfaces to be investigated and compared. Notes the variety of purposes for which transaction logging is undertaken (recovery, playback or analysis), and the corresponding variety of methods and formats employed. Presents a series of examples illustrating logging for both character based and GUI systems, and demonstrating the usefulness of a relational DMBS for storing and analyzing the data. Notes the planned development of logging techniques for distributed versions of Okapi
  
  Inhalt: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/EUM0000000007189.
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research ;
  
  Objekt: Okapi
  
  
• 14
  Karamuftuoglu, M.: Designing language games in Okapi.
  In: Journal of documentation. 53(1997) no.1, S.69-73.
  
  Abstract: Discusses the application of semiotic categories to information retrieval in general, and in particular as developed in a research project being carried out at the Centre for Interactive Systems Research in the Department of Information Science at City University, London, UK. Applies semiotic concepts to information retrieval systems design, within the framework of the Okapi experimental information retrieval system
  
  Inhalt: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/EUM0000000007192.
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research ;
  
  Objekt: Okapi
  
  
• 15
  Kimber, R.T. (Hrsg.): Okapi and information retrieval.[Themenheft].
  In: Journal of documentation. 53(1997) no.1, S.1-87.
  
  Abstract: Thematic issue on Okapi and information retrieval research
  
  Objekt: Okapi
  
  
• 16
  Goker, A.: Context learning in Okapi.
  In: Journal of documentation. 53(1997) no.1, S.80-83.
  
  Abstract: A user who makes repeated use of a retrieval system may be assumed to have a context which is common to successive users, and that an information retrieval system which could make use of this context may be better able to match specific needs. Describes a machine learning approach to inferring the user's context, developed in conjunction with the Okapi information retrieval system. Presents the results of an evaluation experiment. There is scope for information retrieval systems to operate in this way
  
  Inhalt: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/EUM0000000007194.
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research ;
  
  Objekt: Okapi
  
  
• 17
  Keen, M.: ¬The Okapi projects.
  In: Journal of documentation. 53(1997) no.1, S.84-87.
  
  Abstract: Reviews the work of the Okapi projects in the development of user friendly information retrieval systems. Discusses a number of issues concerning information retrieval projects and the methodology used in the evaluation of information retrieval
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research
  
  Objekt: Okapi
  
  
• 18
  Beaulieu, M.M. ; Gatford, M. ; Huang, X. ; Robertson, S.E. ; Walker, S. ; Williams, P.: Okapi an TREC-5.
  In: The Fifth Text Retrieval Conference (TREC-5). Ed.: E.M. Voorhees u. D.K. Harman. Gaithersburgh, MD : National Institute of Standards and Technology, 1997. S.143-165.
  (NIST special publication;)
  
  Themenfeld: Retrievalstudien
  Objekt: TREC ; Okapi
  
  
• 19
  Robertson, S.E.: Overview of the Okapi projects.
  In: Journal of documentation. 53(1997) no.1, S.3-7.
  
  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
  
  Inhalt: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/EUM0000000007186.
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research ;
  
  Objekt: Okapi
  
  
• 20
  Beaulieu, M.: Experiments on interfaces to support query expansion.
  In: Journal of documentation. 53(1997) no.1, S.8-19.
  
  Abstract: Focuses on the user and human-computer interaction (HCI) aspects of the research based on the Okapi text retrieval system. Describes 3 experiments using different approaches to query expansion, highlighting the relationship between the functionality of a system and different interface designs. These experiments involve both automatic and interactive query expansion, and both character based and GUI (graphical user interface) environments. The effectiveness of the search interaction for query expansion depends on resolving opposing interface and functional aspects, e.g. automatic vs. interactive query expansion, explicit vs. implicit use of a thesaurus, and document vs. query space
  
  Inhalt: Vgl. auch unter: http://www.emeraldinsight.com/10.1108/EUM0000000007187.
  
  Anmerkung: Contribution to a thematic issue on Okapi and information retrieval research ;
  
  Themenfeld: OPAC ; Suchoberflächen ; Semantisches Umfeld in Indexierung u. Retrieval
  Objekt: Okapi