Search (62 results, page 1 of 4)

  • × theme_ss:"Retrievalalgorithmen"
  1. Shiri, A.A.; Revie, C.: Query expansion behavior within a thesaurus-enhanced search environment : a user-centered evaluation (2006) 0.03
    0.031199675 = product of:
      0.06239935 = sum of:
        0.06239935 = sum of:
          0.031563994 = weight(_text_:b in 56) [ClassicSimilarity], result of:
            0.031563994 = score(doc=56,freq=2.0), product of:
              0.16126883 = queryWeight, product of:
                3.542962 = idf(docFreq=3476, maxDocs=44218)
                0.045518078 = queryNorm
              0.19572285 = fieldWeight in 56, product of:
                1.4142135 = tf(freq=2.0), with freq of:
                  2.0 = termFreq=2.0
                3.542962 = idf(docFreq=3476, maxDocs=44218)
                0.0390625 = fieldNorm(doc=56)
          0.030835358 = weight(_text_:22 in 56) [ClassicSimilarity], result of:
            0.030835358 = score(doc=56,freq=2.0), product of:
              0.15939656 = queryWeight, product of:
                3.5018296 = idf(docFreq=3622, maxDocs=44218)
                0.045518078 = queryNorm
              0.19345059 = fieldWeight in 56, product of:
                1.4142135 = tf(freq=2.0), with freq of:
                  2.0 = termFreq=2.0
                3.5018296 = idf(docFreq=3622, maxDocs=44218)
                0.0390625 = fieldNorm(doc=56)
      0.5 = coord(1/2)
    
    Abstract
    The study reported here investigated the query expansion behavior of end-users interacting with a thesaurus-enhanced search system on the Web. Two groups, namely academic staff and postgraduate students, were recruited into this study. Data were collected from 90 searches performed by 30 users using the OVID interface to the CAB abstracts database. Data-gathering techniques included questionnaires, screen capturing software, and interviews. The results presented here relate to issues of search-topic and search-term characteristics, number and types of expanded queries, usefulness of thesaurus terms, and behavioral differences between academic staff and postgraduate students in their interaction. The key conclusions drawn were that (a) academic staff chose more narrow and synonymous terms than did postgraduate students, who generally selected broader and related terms; (b) topic complexity affected users' interaction with the thesaurus in that complex topics required more query expansion and search term selection; (c) users' prior topic-search experience appeared to have a significant effect on their selection and evaluation of thesaurus terms; (d) in 50% of the searches where additional terms were suggested from the thesaurus, users stated that they had not been aware of the terms at the beginning of the search; this observation was particularly noticeable in the case of postgraduate students.
    Date
    22. 7.2006 16:32:43
  2. Voorhees, E.M.: Implementing agglomerative hierarchic clustering algorithms for use in document retrieval (1986) 0.02
    0.024668286 = product of:
      0.04933657 = sum of:
        0.04933657 = product of:
          0.09867314 = sum of:
            0.09867314 = weight(_text_:22 in 402) [ClassicSimilarity], result of:
              0.09867314 = score(doc=402,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.61904186 = fieldWeight in 402, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.125 = fieldNorm(doc=402)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Source
    Information processing and management. 22(1986) no.6, S.465-476
  3. Ziegler, B.: ESS: ein schneller Algorithmus zur Mustersuche in Zeichenfolgen (1996) 0.02
    0.022094795 = product of:
      0.04418959 = sum of:
        0.04418959 = product of:
          0.08837918 = sum of:
            0.08837918 = weight(_text_:b in 7543) [ClassicSimilarity], result of:
              0.08837918 = score(doc=7543,freq=2.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.54802394 = fieldWeight in 7543, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.109375 = fieldNorm(doc=7543)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
  4. Smeaton, A.F.; Rijsbergen, C.J. van: ¬The retrieval effects of query expansion on a feedback document retrieval system (1983) 0.02
    0.02158475 = product of:
      0.0431695 = sum of:
        0.0431695 = product of:
          0.086339 = sum of:
            0.086339 = weight(_text_:22 in 2134) [ClassicSimilarity], result of:
              0.086339 = score(doc=2134,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.5416616 = fieldWeight in 2134, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.109375 = fieldNorm(doc=2134)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    30. 3.2001 13:32:22
  5. Back, J.: ¬An evaluation of relevancy ranking techniques used by Internet search engines (2000) 0.02
    0.02158475 = product of:
      0.0431695 = sum of:
        0.0431695 = product of:
          0.086339 = sum of:
            0.086339 = weight(_text_:22 in 3445) [ClassicSimilarity], result of:
              0.086339 = score(doc=3445,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.5416616 = fieldWeight in 3445, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.109375 = fieldNorm(doc=3445)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    25. 8.2005 17:42:22
  6. Silveira, M.; Ribeiro-Neto, B.: Concept-based ranking : a case study in the juridical domain (2004) 0.02
    0.018938396 = product of:
      0.037876792 = sum of:
        0.037876792 = product of:
          0.075753585 = sum of:
            0.075753585 = weight(_text_:b in 2339) [ClassicSimilarity], result of:
              0.075753585 = score(doc=2339,freq=2.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.46973482 = fieldWeight in 2339, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.09375 = fieldNorm(doc=2339)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
  7. Fuhr, N.: Ranking-Experimente mit gewichteter Indexierung (1986) 0.02
    0.018501213 = product of:
      0.037002426 = sum of:
        0.037002426 = product of:
          0.07400485 = sum of:
            0.07400485 = weight(_text_:22 in 58) [ClassicSimilarity], result of:
              0.07400485 = score(doc=58,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.46428138 = fieldWeight in 58, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.09375 = fieldNorm(doc=58)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    14. 6.2015 22:12:44
  8. Fuhr, N.: Rankingexperimente mit gewichteter Indexierung (1986) 0.02
    0.018501213 = product of:
      0.037002426 = sum of:
        0.037002426 = product of:
          0.07400485 = sum of:
            0.07400485 = weight(_text_:22 in 2051) [ClassicSimilarity], result of:
              0.07400485 = score(doc=2051,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.46428138 = fieldWeight in 2051, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.09375 = fieldNorm(doc=2051)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    14. 6.2015 22:12:56
  9. Chang, R.: ¬The development of indexing technology (1993) 0.02
    0.017855292 = product of:
      0.035710584 = sum of:
        0.035710584 = product of:
          0.07142117 = sum of:
            0.07142117 = weight(_text_:b in 7024) [ClassicSimilarity], result of:
              0.07142117 = score(doc=7024,freq=4.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.44287026 = fieldWeight in 7024, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.0625 = fieldNorm(doc=7024)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    Reviews the basic techniques of computerized indexing, including various file accessing methods such as: Sequential Access Method (SAM); Direct Access Method (DAM); Indexed Sequential Access Method (ISAM), and Virtual Indexed Sequential Access Method (VSAM); and various B-tree (balanced tree)structures. Illustrates how records are stored and accessed, and how B-trees are used to for improving the operations of information retrieval and maintenance
  10. Chang, R.: Keyword searching and indexing (1993) 0.02
    0.017855292 = product of:
      0.035710584 = sum of:
        0.035710584 = product of:
          0.07142117 = sum of:
            0.07142117 = weight(_text_:b in 7223) [ClassicSimilarity], result of:
              0.07142117 = score(doc=7223,freq=4.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.44287026 = fieldWeight in 7223, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.0625 = fieldNorm(doc=7223)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    Explains how a computer indexing system works. Reviews fundamentals of how data are stored and retrieved by computers. Describes B-Tree and B+-Tree indexing structures. Gives basic keyword searching techniques that the user must apply to make use of the indexing programs. The demand for keyword retrieval is increasing and librarians should expect to see the keyword-indexing feature become commonly available
  11. Quint, B.: Check out the new RANK command on DIALOG (1993) 0.02
    0.015781997 = product of:
      0.031563994 = sum of:
        0.031563994 = product of:
          0.06312799 = sum of:
            0.06312799 = weight(_text_:b in 6640) [ClassicSimilarity], result of:
              0.06312799 = score(doc=6640,freq=2.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.3914457 = fieldWeight in 6640, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.078125 = fieldNorm(doc=6640)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
  12. 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) 0.02
    0.015781997 = product of:
      0.031563994 = sum of:
        0.031563994 = product of:
          0.06312799 = sum of:
            0.06312799 = weight(_text_:b in 1696) [ClassicSimilarity], result of:
              0.06312799 = score(doc=1696,freq=2.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.3914457 = fieldWeight in 1696, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.078125 = fieldNorm(doc=1696)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
  13. 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
    0.013391469 = product of:
      0.026782937 = sum of:
        0.026782937 = product of:
          0.053565875 = sum of:
            0.053565875 = weight(_text_:b in 4119) [ClassicSimilarity], result of:
              0.053565875 = score(doc=4119,freq=4.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.3321527 = fieldWeight in 4119, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.046875 = fieldNorm(doc=4119)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    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.
  14. Chakrabarti, S.; Dom, B.; Kumar, S.R.; Raghavan, P.; Rajagopalan, S.; Tomkins, A.; Kleinberg, J.M.; Gibson, D.: Neue Pfade durch den Internet-Dschungel : Die zweite Generation von Web-Suchmaschinen (1999) 0.01
    0.012625597 = product of:
      0.025251195 = sum of:
        0.025251195 = product of:
          0.05050239 = sum of:
            0.05050239 = weight(_text_:b in 3) [ClassicSimilarity], result of:
              0.05050239 = score(doc=3,freq=2.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.31315655 = fieldWeight in 3, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.0625 = fieldNorm(doc=3)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
  15. Behnert, C.; Borst, T.: Neue Formen der Relevanz-Sortierung in bibliothekarischen Informationssystemen : das DFG-Projekt LibRank (2015) 0.01
    0.012625597 = product of:
      0.025251195 = sum of:
        0.025251195 = product of:
          0.05050239 = sum of:
            0.05050239 = weight(_text_:b in 5392) [ClassicSimilarity], result of:
              0.05050239 = score(doc=5392,freq=2.0), product of:
                0.16126883 = queryWeight, product of:
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.045518078 = queryNorm
                0.31315655 = fieldWeight in 5392, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.542962 = idf(docFreq=3476, maxDocs=44218)
                  0.0625 = fieldNorm(doc=5392)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    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.
  16. MacFarlane, A.; Robertson, S.E.; McCann, J.A.: Parallel computing for passage retrieval (2004) 0.01
    0.012334143 = product of:
      0.024668286 = sum of:
        0.024668286 = product of:
          0.04933657 = sum of:
            0.04933657 = weight(_text_:22 in 5108) [ClassicSimilarity], result of:
              0.04933657 = score(doc=5108,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.30952093 = fieldWeight in 5108, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0625 = fieldNorm(doc=5108)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    20. 1.2007 18:30:22
  17. Faloutsos, C.: Signature files (1992) 0.01
    0.012334143 = product of:
      0.024668286 = sum of:
        0.024668286 = product of:
          0.04933657 = sum of:
            0.04933657 = weight(_text_:22 in 3499) [ClassicSimilarity], result of:
              0.04933657 = score(doc=3499,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.30952093 = fieldWeight in 3499, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0625 = fieldNorm(doc=3499)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    7. 5.1999 15:22:48
  18. Losada, D.E.; Barreiro, A.: Emebedding term similarity and inverse document frequency into a logical model of information retrieval (2003) 0.01
    0.012334143 = product of:
      0.024668286 = sum of:
        0.024668286 = product of:
          0.04933657 = sum of:
            0.04933657 = weight(_text_:22 in 1422) [ClassicSimilarity], result of:
              0.04933657 = score(doc=1422,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.30952093 = fieldWeight in 1422, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0625 = fieldNorm(doc=1422)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    22. 3.2003 19:27:23
  19. Bornmann, L.; Mutz, R.: From P100 to P100' : a new citation-rank approach (2014) 0.01
    0.012334143 = product of:
      0.024668286 = sum of:
        0.024668286 = product of:
          0.04933657 = sum of:
            0.04933657 = weight(_text_:22 in 1431) [ClassicSimilarity], result of:
              0.04933657 = score(doc=1431,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.30952093 = fieldWeight in 1431, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0625 = fieldNorm(doc=1431)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    22. 8.2014 17:05:18
  20. Tober, M.; Hennig, L.; Furch, D.: SEO Ranking-Faktoren und Rang-Korrelationen 2014 : Google Deutschland (2014) 0.01
    0.012334143 = product of:
      0.024668286 = sum of:
        0.024668286 = product of:
          0.04933657 = sum of:
            0.04933657 = weight(_text_:22 in 1484) [ClassicSimilarity], result of:
              0.04933657 = score(doc=1484,freq=2.0), product of:
                0.15939656 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.045518078 = queryNorm
                0.30952093 = fieldWeight in 1484, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0625 = fieldNorm(doc=1484)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Date
    13. 9.2014 14:45:22

Years

Languages

  • e 51
  • d 11

Types

  • a 59
  • m 1
  • r 1
  • x 1
  • More… Less…