Search (17 results, page 1 of 1)

  • × theme_ss:"Retrievalalgorithmen"
  • × year_i:[2010 TO 2020}
  1. Karlsson, A.; Hammarfelt, B.; Steinhauer, H.J.; Falkman, G.; Olson, N.; Nelhans, G.; Nolin, J.: Modeling uncertainty in bibliometrics and information retrieval : an information fusion approach (2015) 0.01 
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  2. Moura, E.S. de; Fernandes, D.; Ribeiro-Neto, B.; Silva, A.S. da; Gonçalves, M.A.: Using structural information to improve search in Web collections (2010) 0.01 
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    Abstract
    In this work, we investigate the problem of using the block structure of Web pages to improve ranking results. Starting with basic intuitions provided by the concepts of term frequency (TF) and inverse document frequency (IDF), we propose nine block-weight functions to distinguish the impact of term occurrences inside page blocks, instead of inside whole pages. These are then used to compute a modified BM25 ranking function. Using four distinct Web collections, we ran extensive experiments to compare our block-weight ranking formulas with two other baselines: (a) a BM25 ranking applied to full pages, and (b) a BM25 ranking that takes into account best blocks. Our methods suggest that our block-weighting ranking method is superior to all baselines across all collections we used and that average gain in precision figures from 5 to 20% are generated.
  3. Mayr, P.: Bradfordizing als Re-Ranking-Ansatz in Literaturinformationssystemen (2011) 0.01 
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    Abstract
    In diesem Artikel wird ein Re-Ranking-Ansatz für Suchsysteme vorgestellt, der die Recherche nach wissenschaftlicher Literatur messbar verbessern kann. Das nichttextorientierte Rankingverfahren Bradfordizing wird eingeführt und anschließend im empirischen Teil des Artikels bzgl. der Effektivität für typische fachbezogene Recherche-Topics evaluiert. Dem Bradford Law of Scattering (BLS), auf dem Bradfordizing basiert, liegt zugrunde, dass sich die Literatur zu einem beliebigen Fachgebiet bzw. -thema in Zonen unterschiedlicher Dokumentenkonzentration verteilt. Dem Kernbereich mit hoher Konzentration der Literatur folgen Bereiche mit mittlerer und geringer Konzentration. Bradfordizing sortiert bzw. rankt eine Dokumentmenge damit nach den sogenannten Kernzeitschriften. Der Retrievaltest mit 164 intellektuell bewerteten Fragestellungen in Fachdatenbanken aus den Bereichen Sozial- und Politikwissenschaften, Wirtschaftswissenschaften, Psychologie und Medizin zeigt, dass die Dokumente der Kernzeitschriften signifikant häufiger relevant bewertet werden als Dokumente der zweiten Dokumentzone bzw. den Peripherie-Zeitschriften. Die Implementierung von Bradfordizing und weiteren Re-Rankingverfahren liefert unmittelbare Mehrwerte für den Nutzer.
  4. Behnert, C.; Borst, T.: Neue Formen der Relevanz-Sortierung in bibliothekarischen Informationssystemen : das DFG-Projekt LibRank (2015) 0.01 
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    Abstract
    Das von der DFG geförderte Projekt LibRank erforscht neue Rankingverfahren für bibliothekarische Informationssysteme, die aufbauend auf Erkenntnissen aus dem Bereich Websuche qualitätsinduzierende Faktoren wie z. B. Aktualität, Popularität und Verfügbarkeit von einzelnen Medien berücksichtigen. Die konzipierten Verfahren werden im Kontext eines in den Wirtschaftswissenschaften häufig genutzten Rechercheportals (EconBiz) entwickelt und in einem Testsystem systematisch evaluiert. Es werden Rankingfaktoren, die für den Bibliotheksbereich von besonderem Interesse sind, vorgestellt und exemplarisch Probleme und Herausforderungen aufgezeigt.
  5. Dang, E.K.F.; Luk, R.W.P.; Allan, J.; Ho, K.S.; Chung, K.F.L.; Lee, D.L.: ¬A new context-dependent term weight computed by boost and discount using relevance information (2010) 0.01 
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    Abstract
    We studied the effectiveness of a new class of context-dependent term weights for information retrieval. Unlike the traditional term frequency-inverse document frequency (TF-IDF), the new weighting of a term t in a document d depends not only on the occurrence statistics of t alone but also on the terms found within a text window (or "document-context") centered on t. We introduce a Boost and Discount (B&D) procedure which utilizes partial relevance information to compute the context-dependent term weights of query terms according to a logistic regression model. We investigate the effectiveness of the new term weights compared with the context-independent BM25 weights in the setting of relevance feedback. We performed experiments with title queries of the TREC-6, -7, -8, and 2005 collections, comparing the residual Mean Average Precision (MAP) measures obtained using B&D term weights and those obtained by a baseline using BM25 weights. Given either 10 or 20 relevance judgments of the top retrieved documents, using the new term weights yields improvement over the baseline for all collections tested. The MAP obtained with the new weights has relative improvement over the baseline by 3.3 to 15.2%, with statistical significance at the 95% confidence level across all four collections.
  6. Jacucci, G.; Barral, O.; Daee, P.; Wenzel, M.; Serim, B.; Ruotsalo, T.; Pluchino, P.; Freeman, J.; Gamberini, L.; Kaski, S.; Blankertz, B.: Integrating neurophysiologic relevance feedback in intent modeling for information retrieval (2019) 0.01 
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  7. Hora, M.: Methoden für das Ranking in Discovery-Systemen (2018) 0.01 
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    Abstract
    Discovery-Systeme bieten meist als Standardeinstellung eine Sortierung nach Relevanz an. Wie die Relevanz ermittelt wird, ist häufig intransparent. Dabei wären Kenntnisse darüber aus Nutzersicht ein wichtiger Faktor in der Informationskompetenz, während Bibliotheken sicherstellen sollten, dass das Ranking zum eigenen Bestand und Publikum passt. In diesem Aufsatz wird dargestellt, wie Discovery-Systeme Treffer auswählen und bewerten. Dazu gehören Indexierung, Prozessierung, Text-Matching und weitere Relevanzkriterien, z. B. Popularität oder Verfügbarkeit. Schließlich müssen alle betrachteten Kriterien zu einem zentralen Score zusammengefasst werden. Ein besonderer Fokus wird auf das Ranking von EBSCO Discovery Service, Primo und Summon gelegt.
  8. Behnert, C.; Plassmeier, K.; Borst, T.; Lewandowski, D.: Evaluierung von Rankingverfahren für bibliothekarische Informationssysteme (2019) 0.01 
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    Abstract
    Dieser Beitrag beschreibt eine Studie zur Entwicklung und Evaluierung von Rankingverfahren für bibliothekarische Informationssysteme. Dazu wurden mögliche Faktoren für das Relevanzranking ausgehend von den Verfahren in Websuchmaschinen identifiziert, auf den Bibliothekskontext übertragen und systematisch evaluiert. Mithilfe eines Testsystems, das auf dem ZBW-Informationsportal EconBiz und einer web-basierten Software zur Evaluierung von Suchsystemen aufsetzt, wurden verschiedene Relevanzfaktoren (z. B. Popularität in Verbindung mit Aktualität) getestet. Obwohl die getesteten Rankingverfahren auf einer theoretischen Ebene divers sind, konnten keine einheitlichen Verbesserungen gegenüber den Baseline-Rankings gemessen werden. Die Ergebnisse deuten darauf hin, dass eine Adaptierung des Rankings auf individuelle Nutzer bzw. Nutzungskontexte notwendig sein könnte, um eine höhere Performance zu erzielen.
  9. Cecchini, R.L.; Lorenzetti, C.M.; Maguitman, A.G.; Brignole, N.B.: Multiobjective evolutionary algorithms for context-based search (2010) 0.01 
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    Abstract
    Formulating high-quality queries is a key aspect of context-based search. However, determining the effectiveness of a query is challenging because multiple objectives, such as high precision and high recall, are usually involved. In this work, we study techniques that can be applied to evolve contextualized queries when the criteria for determining query quality are based on multiple objectives. We report on the results of three different strategies for evolving queries: (a) single-objective, (b) multiobjective with Pareto-based ranking, and (c) multiobjective with aggregative ranking. After a comprehensive evaluation with a large set of topics, we discuss the limitations of the single-objective approach and observe that both the Pareto-based and aggregative strategies are highly effective for evolving topical queries. In particular, our experiments lead us to conclude that the multiobjective techniques are superior to a baseline as well as to well-known and ad hoc query reformulation techniques.
  10. Van der Veer Martens, B.; Fleet, C. van: Opening the black box of "relevance work" : a domain analysis (2012) 0.01 
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  11. Symonds, M.; Bruza, P.; Zuccon, G.; Koopman, B.; Sitbon, L.; Turner, I.: Automatic query expansion : a structural linguistic perspective (2014) 0.00 
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  12. Xu, B.; Lin, H.; Lin, Y.: Assessment of learning to rank methods for query expansion (2016) 0.00 
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  13. Bornmann, L.; Mutz, R.: From P100 to P100' : a new citation-rank approach (2014) 0.00 
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    Date
    22. 8.2014 17:05:18
  14. Tober, M.; Hennig, L.; Furch, D.: SEO Ranking-Faktoren und Rang-Korrelationen 2014 : Google Deutschland (2014) 0.00 
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    Date
    13. 9.2014 14:45:22
  15. Ravana, S.D.; Rajagopal, P.; Balakrishnan, V.: Ranking retrieval systems using pseudo relevance judgments (2015) 0.00 
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    Date
    20. 1.2015 18:30:22
    18. 9.2018 18:22:56
  16. Baloh, P.; Desouza, K.C.; Hackney, R.: Contextualizing organizational interventions of knowledge management systems : a design science perspectiveA domain analysis (2012) 0.00 
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    Date
    11. 6.2012 14:22:34
  17. Soulier, L.; Jabeur, L.B.; Tamine, L.; Bahsoun, W.: On ranking relevant entities in heterogeneous networks using a language-based model (2013) 0.00 
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    Date
    22. 3.2013 19:34:49

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