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  • × author_ss:"Ferber, R."
  1. Ferber, R.: Automated indexing with thesaurus descriptors : a co-occurence based approach to multilingual retrieval (1997) 0.00 
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    Abstract
    Indexing documents with descriptors from a multilingual thesaurus is an approach to multilingual information retrieval. However, manual indexing is expensive. Automazed indexing methods in general use terms found in the document. Thesaurus descriptors are complex terms that are often not used in documents or have specific meanings within the thesaurus; therefore most weighting schemes of automated indexing methods are not suited to select thesaurus descriptors. In this paper a linear associative system is described that uses similarity values extracted from a large corpus of manually indexed documents to construct a rank ordering of the descriptors for a given document title. The system is adaptive and has to be tuned with a training sample of records for the specific task. The system was tested on a corpus of some 80.000 bibliographic records. The results show a high variability with changing parameter values. This indicated that it is very important to empirically adapt the model to the specific situation it is used in. The overall median of the manually assigned descriptors in the automatically generated ranked list of all 3.631 descriptors is 14 for the set used to adapt the system and 11 for a test set not used in the optimization process. This result shows that the optimization is not a fitting to a specific training set but a real adaptation of the model to the setting
    Type
    a
  2. Ferber, R.: Vorhersage der Suchwortwahl von professionellen Rechercheuren in Literaturdatenbanken durch assoziative Netze (1992) 0.00 
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    Source
    Mensch und Maschine: Informationelle Schnittstellen der Kommunikation. Proc. des 3. Int. Symposiums für Informationswissenschaft (ISI'92), 5.-7.11.1992 in Saarbrücken. Hrsg.: H.H. Zimmermann, H.-D. Luckhardt u. A. Schulz
    Type
    a
  3. Wettler, M.; Rapp, R.; Ferber, R.: Freie Assoziationen und Kontiguitäten von Wörtern in Texten (1993) 0.00 
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    Type
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  4. Ferber, R.; Wettler, M.; Rapp, R.: ¬An associative model of word selection in the generation of search queries (1995) 0.00 
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    Abstract
    To generate a search query based on an end user request, a database searcher has to select appropriate search terms. These terms can either be taken from the request, or they can be added by the searcher. This selection process is simulated by an associative lexical net; the nodes of the net are the terms used in 94 records of written requests to a psychological information agency and the respective online searches. The weights connecting the nodes are calculated from the co-occurrences of these terms in the abstracts of the database PsycLit. To simulate the term selection process of a query, the nodes of all terms used in the written requests are activated, and 1 or more spreading activation cycles are performed. The result of the simulation is a ranking of the terms according to the activities of their nodes. Simulations for all 94 records show a low mean activity rank for the terms selected from the request; the mean activity rank for new terms added by the searcher is lower than the mean activity rank for thode terms of the request that were not used in the query
    Type
    a
  5. Ferber, R.: Dokumentsuche und Dokumenterschließung (1999) 0.00 
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  6. Koschinsky, G.; Ferber, R.: Kommunikationswege beim E-Learning : eine empirische Untersuchung an der Hochschule Darmstadt (2007) 0.00 
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    Type
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