Search (19 results, page 1 of 1)

  • × year_i:[2000 TO 2010}
  • × theme_ss:"Retrievalalgorithmen"
  1. Mutschke, P.: Autorennetzwerke : Verfahren zur Netzwerkanalyse als Mehrwertdienste für Informationssysteme (2004) 0.02 
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    Abstract
    Virtuelle Bibliotheken enthalten eine Fülle an Informationen, die in ihrer Vielfalt und Tiefe von Standardsuchmaschinen nicht erschöpfend erfasst wird. Der Arbeitsbericht informiert über Entwicklungen am IZ, die darauf abzielen, Wissen über das Interaktionsgeschehen in wissenschaftlichen Communities und den sozialen Status ihrer Akteure für das Retrieval auszunutzen. Grundlage hierfür sind soziale Netzwerke, die sich durch Kooperation der wissenschaftlichen Akteure konstituieren und in den Dokumenten der Datenbasis z.B. als Koautorbeziehungen repräsentiert sind (Autorennetzwerke). Die in dem Bericht beschriebenen Studien zur Small-World-Topologie von Autorennetzwerken zeigen, dass diese Netzwerke ein erhebliches Potential für Informationssysteme haben. Der Bericht diskutiert Szenarios, die beschreiben, wie Autorennetzwerke und hier insbesondere das Konzept der Akteurszentralität für die Informationssuche in Datenbanken sinnvoll genutzt werden können. Kernansatz dieser Retrievalmodelle ist die Suche nach Experten und das Ranking von Dokumenten auf der Basis der Zentralität von Autoren in Autorennetzwerken.
  2. Lavrenko, V.: ¬A generative theory of relevance (2009) 0.02 
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    BK
    06.74 / Informationssysteme
    Classification
    06.74 / Informationssysteme
  3. Berry, M.W.; Browne, M.: Understanding search engines : mathematical modeling and text retrieval (2005) 0.02 
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    06.74 / Informationssysteme
    Classification
    06.74 / Informationssysteme
  4. Back, J.: ¬An evaluation of relevancy ranking techniques used by Internet search engines (2000) 0.01 
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    Date
    25. 8.2005 17:42:22
  5. Langville, A.N.; Meyer, C.D.: Google's PageRank and beyond : the science of search engine rankings (2006) 0.01 
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    06.74 / Informationssysteme
    Classification
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  6. Mayr, P.: Re-Ranking auf Basis von Bradfordizing für die verteilte Suche in Digitalen Bibliotheken (2009) 0.01 
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    Abstract
    Trotz großer Dokumentmengen für datenbankübergreifende Literaturrecherchen erwarten akademische Nutzer einen möglichst hohen Anteil an relevanten und qualitativen Dokumenten in den Trefferergebnissen. Insbesondere die Reihenfolge und Struktur der gelisteten Ergebnisse (Ranking) spielt, neben dem direkten Volltextzugriff auf die Dokumente, inzwischen eine entscheidende Rolle beim Design von Suchsystemen. Nutzer erwarten weiterhin flexible Informationssysteme, die es unter anderem zulassen, Einfluss auf das Ranking der Dokumente zu nehmen bzw. alternative Rankingverfahren zu verwenden. In dieser Arbeit werden zwei Mehrwertverfahren für Suchsysteme vorgestellt, die die typischen Probleme bei der Recherche nach wissenschaftlicher Literatur behandeln und damit die Recherchesituation messbar verbessern können. Die beiden Mehrwertdienste semantische Heterogenitätsbehandlung am Beispiel Crosskonkordanzen und Re-Ranking auf Basis von Bradfordizing, die in unterschiedlichen Phasen der Suche zum Einsatz kommen, werden hier ausführlich beschrieben und im empirischen Teil der Arbeit bzgl. der Effektivität für typische fachbezogene Recherchen evaluiert. Vorrangiges Ziel der Promotion ist es, zu untersuchen, ob das hier vorgestellte alternative Re-Rankingverfahren Bradfordizing im Anwendungsbereich bibliographischer Datenbanken zum einen operabel ist und zum anderen voraussichtlich gewinnbringend in Informationssystemen eingesetzt und dem Nutzer angeboten werden kann. Für die Tests wurden Fragestellungen und Daten aus zwei Evaluationsprojekten (CLEF und KoMoHe) verwendet. Die intellektuell bewerteten Dokumente stammen aus insgesamt sieben wissenschaftlichen Fachdatenbanken der Fächer Sozialwissenschaften, Politikwissenschaft, Wirtschaftswissenschaften, Psychologie und Medizin. Die Evaluation der Crosskonkordanzen (insgesamt 82 Fragestellungen) zeigt, dass sich die Retrievalergebnisse signifikant für alle Crosskonkordanzen verbessern; es zeigt sich zudem, dass interdisziplinäre Crosskonkordanzen den stärksten (positiven) Effekt auf die Suchergebnisse haben. Die Evaluation des Re-Ranking nach Bradfordizing (insgesamt 164 Fragestellungen) zeigt, dass die Dokumente der Kernzone (Kernzeitschriften) für die meisten Testreihen eine signifikant höhere Precision als Dokumente der Zone 2 und Zone 3 (Peripheriezeitschriften) ergeben. Sowohl für Zeitschriften als auch für Monographien kann dieser Relevanzvorteil nach Bradfordizing auf einer sehr breiten Basis von Themen und Fragestellungen an zwei unabhängigen Dokumentkorpora empirisch nachgewiesen werden.
  7. MacFarlane, A.; Robertson, S.E.; McCann, J.A.: Parallel computing for passage retrieval (2004) 0.01 
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    Date
    20. 1.2007 18:30:22
  8. Losada, D.E.; Barreiro, A.: Emebedding term similarity and inverse document frequency into a logical model of information retrieval (2003) 0.01 
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    Date
    22. 3.2003 19:27:23
  9. Kanaeva, Z.: Ranking: Google und CiteSeer (2005) 0.01 
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    Date
    20. 3.2005 16:23:22
  10. Crestani, F.; Dominich, S.; Lalmas, M.; Rijsbergen, C.J.K. van: Mathematical, logical, and formal methods in information retrieval : an introduction to the special issue (2003) 0.01 
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    Date
    22. 3.2003 19:27:36
  11. Fan, W.; Fox, E.A.; Pathak, P.; Wu, H.: ¬The effects of fitness functions an genetic programming-based ranking discovery for Web search (2004) 0.01 
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    Date
    31. 5.2004 19:22:06
  12. Furner, J.: ¬A unifying model of document relatedness for hybrid search engines (2003) 0.01 
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    Date
    11. 9.2004 17:32:22
  13. Witschel, H.F.: Global term weights in distributed environments (2008) 0.01 
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    Date
    1. 8.2008 9:44:22
  14. Klas, C.-P.; Fuhr, N.; Schaefer, A.: Evaluating strategic support for information access in the DAFFODIL system (2004) 0.01 
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    Date
    16.11.2008 16:22:48
  15. Campos, L.M. de; Fernández-Luna, J.M.; Huete, J.F.: Implementing relevance feedback in the Bayesian network retrieval model (2003) 0.01 
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    Date
    22. 3.2003 19:30:19
  16. Song, D.; Bruza, P.D.: Towards context sensitive information inference (2003) 0.01 
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    22. 3.2003 19:35:46
  17. Shiri, A.A.; Revie, C.: Query expansion behavior within a thesaurus-enhanced search environment : a user-centered evaluation (2006) 0.01 
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    Date
    22. 7.2006 16:32:43
  18. Dominich, S.: Mathematical foundations of information retrieval (2001) 0.01 
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    22. 3.2008 12:26:32
  19. Khoo, C.S.G.; Wan, K.-W.: ¬A simple relevancy-ranking strategy for an interface to Boolean OPACs (2004) 0.00 
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    Source
    Electronic library. 22(2004) no.2, S.112-120

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