Search (4 results, page 1 of 1)

  • × theme_ss:"Suchmaschinen"
  • × theme_ss:"Retrievalstudien"
  1. Eastman, C.M.: 30,000 hits may be better than 300 : precision anomalies in Internet searches (2002) 0.02 
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    Abstract
    In this issue we begin with a paper where Eastman points out that conventional narrower queries (the use of conjunctions and phrases) in a web engine search will reduce returned number of hits but not necessarily increase precision in the top ranked documents in the return. Thus by precision anomalies Eastman means that search narrowing activity results in no precision change or a decrease in precision. Multiple queries with multiple engines were run by students for a three-year period and the formulation/engine combination was recorded as was the number of hits. Relevance was also recorded for the top ten and top twenty ranked retrievals. While narrower searches reduced total hits they did not usually improve precision. Initial high precision and poor query reformulation account for some of the results, as did Alta Vista's failure to use the ranking algorithm incorporated in its regular search in its advanced search feature. However, since the top listed returns often reoccurred in all formulations, it would seem that the ranking algorithms are doing a consistent job of practical precision ranking that is not improved by reformulation.
  2. Bar-Ilan, J.: Methods for measuring search engine performance over time (2002) 0.00 
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    Date
    23. 3.2002 9:50:29
  3. Dresel, R.; Hörnig, D.; Kaluza, H.; Peter, A.; Roßmann, A.; Sieber, W.: Evaluation deutscher Web-Suchwerkzeuge : Ein vergleichender Retrievaltest (2001) 0.00 
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    Abstract
    Die deutschen Suchmaschinen, Abacho, Acoon, Fireball und Lycos sowie die Web-Kataloge Web.de und Yahoo! werden einem Qualitätstest nach relativem Recall, Precision und Availability unterzogen. Die Methoden der Retrievaltests werden vorgestellt. Im Durchschnitt werden bei einem Cut-Off-Wert von 25 ein Recall von rund 22%, eine Precision von knapp 19% und eine Verfügbarkeit von 24% erreicht
  4. Günther, M.: Vermitteln Suchmaschinen vollständige Bilder aktueller Themen? : Untersuchung der Gewichtung inhaltlicher Aspekte von Suchmaschinenergebnissen in Deutschland und den USA (2016) 0.00 
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    Source
    Young information scientists. 1(2016), S.13-29

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