Search (30 results, page 1 of 2)

  • × theme_ss:"Citation indexing"
  • × theme_ss:"Informetrie"
  1. Nicolaisen, J.: Citation analysis (2007) 0.01 
    0.0056086862 = product of:
  0.0392608 = sum of:
    0.0392608 = product of:
      0.0785216 = sum of:
        0.0785216 = weight(_text_:22 in 6091) [ClassicSimilarity], result of:
          0.0785216 = score(doc=6091,freq=2.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.61904186 = fieldWeight in 6091, 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=6091)
      0.5 = coord(1/2)
  0.14285715 = coord(1/7)
    Date
    13. 7.2008 19:53:22
  2. Van der Veer Martens, B.: Do citation systems represent theories of truth? (2001) 0.00 
    0.004957425 = product of:
  0.034701973 = sum of:
    0.034701973 = product of:
      0.06940395 = sum of:
        0.06940395 = weight(_text_:22 in 3925) [ClassicSimilarity], result of:
          0.06940395 = score(doc=3925,freq=4.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.54716086 = fieldWeight in 3925, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.078125 = fieldNorm(doc=3925)
      0.5 = coord(1/2)
  0.14285715 = coord(1/7)
    Date
    22. 7.2006 15:22:28
  3. Ahlgren, P.; Jarneving, B.; Rousseau, R.: Requirements for a cocitation similarity measure, with special reference to Pearson's correlation coefficient (2003) 0.00 
    0.003641347 = product of:
  0.012744714 = sum of:
    0.0029295133 = product of:
      0.014647567 = sum of:
        0.014647567 = weight(_text_:retrieval in 5171) [ClassicSimilarity], result of:
          0.014647567 = score(doc=5171,freq=2.0), product of:
            0.109568894 = queryWeight, product of:
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.03622214 = queryNorm
            0.13368362 = fieldWeight in 5171, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.03125 = fieldNorm(doc=5171)
      0.2 = coord(1/5)
    0.0098152 = product of:
      0.0196304 = sum of:
        0.0196304 = weight(_text_:22 in 5171) [ClassicSimilarity], result of:
          0.0196304 = score(doc=5171,freq=2.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.15476047 = fieldWeight in 5171, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03125 = fieldNorm(doc=5171)
      0.5 = coord(1/2)
  0.2857143 = coord(2/7)
    Abstract
    Ahlgren, Jarneving, and. Rousseau review accepted procedures for author co-citation analysis first pointing out that since in the raw data matrix the row and column values are identical i,e, the co-citation count of two authors, there is no clear choice for diagonal values. They suggest the number of times an author has been co-cited with himself excluding self citation rather than the common treatment as zeros or as missing values. When the matrix is converted to a similarity matrix the normal procedure is to create a matrix of Pearson's r coefficients between data vectors. Ranking by r and by co-citation frequency and by intuition can easily yield three different orders. It would seem necessary that the adding of zeros to the matrix will not affect the value or the relative order of similarity measures but it is shown that this is not the case with Pearson's r. Using 913 bibliographic descriptions form the Web of Science of articles form JASIS and Scientometrics, authors names were extracted, edited and 12 information retrieval authors and 12 bibliometric authors each from the top 100 most cited were selected. Co-citation and r value (diagonal elements treated as missing) matrices were constructed, and then reconstructed in expanded form. Adding zeros can both change the r value and the ordering of the authors based upon that value. A chi-squared distance measure would not violate these requirements, nor would the cosine coefficient. It is also argued that co-citation data is ordinal data since there is no assurance of an absolute zero number of co-citations, and thus Pearson is not appropriate. The number of ties in co-citation data make the use of the Spearman rank order coefficient problematic.
    Date
    9. 7.2006 10:22:35
  4. Lin, X.; White, H.D.; Buzydlowski, J.: Real-time author co-citation mapping for online searching (2003) 0.00 
    0.0031803926 = product of:
  0.022262746 = sum of:
    0.022262746 = product of:
      0.055656865 = sum of:
        0.02197135 = weight(_text_:retrieval in 1080) [ClassicSimilarity], result of:
          0.02197135 = score(doc=1080,freq=2.0), product of:
            0.109568894 = queryWeight, product of:
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.03622214 = queryNorm
            0.20052543 = fieldWeight in 1080, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.046875 = fieldNorm(doc=1080)
        0.033685513 = weight(_text_:system in 1080) [ClassicSimilarity], result of:
          0.033685513 = score(doc=1080,freq=4.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.29527056 = fieldWeight in 1080, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.046875 = fieldNorm(doc=1080)
      0.4 = coord(2/5)
  0.14285715 = coord(1/7)
    Abstract
    Author searching is traditionally based on the matching of name strings. Special characteristics of authors as personal names and subject indicators are not considered. This makes it difficult to identify a set of related authors or to group authors by subjects in retrieval systems. In this paper, we describe the design and implementation of a prototype visualization system to enhance author searching. The system, called AuthorLink, is based on author co-citation analysis and visualization mapping algorithms such as Kohonen's feature maps and Pathfinder networks. AuthorLink produces interactive author maps in real time from a database of 1.26 million records supplied by the Institute for Scientific Information. The maps show subject groupings and more fine-grained intellectual connections among authors. Through the interactive interface the user can take advantage of such information to refine queries and retrieve documents through point-and-click manipulation of the authors' names.
  5. Larivière, V.; Gingras, Y.; Archambault, E.: ¬The decline in the concentration of citations, 1900-2007 (2009) 0.00 
    0.002974455 = product of:
  0.020821184 = sum of:
    0.020821184 = product of:
      0.041642368 = sum of:
        0.041642368 = weight(_text_:22 in 2763) [ClassicSimilarity], result of:
          0.041642368 = score(doc=2763,freq=4.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.32829654 = fieldWeight in 2763, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=2763)
      0.5 = coord(1/2)
  0.14285715 = coord(1/7)
    Date
    22. 3.2009 19:22:35
  6. Marion, L.S.; McCain, K.W.: Contrasting views of software engineering journals : author cocitation choices and indexer vocabulary assignments (2001) 0.00 
    0.0021805053 = product of:
  0.015263537 = sum of:
    0.015263537 = product of:
      0.03815884 = sum of:
        0.01830946 = weight(_text_:retrieval in 5767) [ClassicSimilarity], result of:
          0.01830946 = score(doc=5767,freq=2.0), product of:
            0.109568894 = queryWeight, product of:
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.03622214 = queryNorm
            0.16710453 = fieldWeight in 5767, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.0390625 = fieldNorm(doc=5767)
        0.01984938 = weight(_text_:system in 5767) [ClassicSimilarity], result of:
          0.01984938 = score(doc=5767,freq=2.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.17398985 = fieldWeight in 5767, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.0390625 = fieldNorm(doc=5767)
      0.4 = coord(2/5)
  0.14285715 = coord(1/7)
    Abstract
    We explore the intellectual subject structure and research themes in software engineering through the identification and analysis of a core journal literature. We examine this literature via two expert perspectives: that of the author, who identified significant work by citing it (journal cocitation analysis), and that of the professional indexer, who tags published work with subject terms to facilitate retrieval from a bibliographic database (subject profile analysis). The data sources are SCISEARCH (the on-line version of Science Citation Index), and INSPEC (a database covering software engineering, computer science, and information systems). We use data visualization tools (cluster analysis, multidimensional scaling, and PFNets) to show the "intellectual maps" of software engineering. Cocitation and subject profile analyses demonstrate that software engineering is a distinct interdisciplinary field, valuing practical and applied aspects, and spanning a subject continuum from "programming-in-the-smalI" to "programming-in-the-large." This continuum mirrors the software development life cycle by taking the operating system or major application from initial programming through project management, implementation, and maintenance. Object orientation is an integral but distinct subject area in software engineering. Key differences are the importance of management and programming: (1) cocitation analysis emphasizes project management and systems development; (2) programming techniques/languages are more influential in subject profiles; (3) cocitation profiles place object-oriented journals separately and centrally while the subject profile analysis locates these journals with the programming/languages group
  7. Chan, H.C.; Kim, H.-W.; Tan, W.C.: Information systems citation patterns from International Conference on Information Systems articles (2006) 0.00 
    0.0021032572 = product of:
  0.0147228 = sum of:
    0.0147228 = product of:
      0.0294456 = sum of:
        0.0294456 = weight(_text_:22 in 201) [ClassicSimilarity], result of:
          0.0294456 = score(doc=201,freq=2.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.23214069 = fieldWeight in 201, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=201)
      0.5 = coord(1/2)
  0.14285715 = coord(1/7)
    Date
    3. 1.2007 17:22:03
  8. H-Index auch im Web of Science (2008) 0.00 
    0.0021032572 = product of:
  0.0147228 = sum of:
    0.0147228 = product of:
      0.0294456 = sum of:
        0.0294456 = weight(_text_:22 in 590) [ClassicSimilarity], result of:
          0.0294456 = score(doc=590,freq=2.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.23214069 = fieldWeight in 590, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=590)
      0.5 = coord(1/2)
  0.14285715 = coord(1/7)
    Date
    6. 4.2008 19:04:22
  9. Mingers, J.; Burrell, Q.L.: Modeling citation behavior in Management Science journals (2006) 0.00 
    0.0021032572 = product of:
  0.0147228 = sum of:
    0.0147228 = product of:
      0.0294456 = sum of:
        0.0294456 = weight(_text_:22 in 994) [ClassicSimilarity], result of:
          0.0294456 = score(doc=994,freq=2.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.23214069 = fieldWeight in 994, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=994)
      0.5 = coord(1/2)
  0.14285715 = coord(1/7)
    Date
    26.12.2007 19:22:05
  10. Fujigaki, Y.: ¬The citation system : citation networks as repeatedly focusing on difference, continuous re-evaluation, and as persistent knowledge accumulation (1998) 0.00 
    0.0018148007 = product of:
  0.012703604 = sum of:
    0.012703604 = product of:
      0.06351802 = sum of:
        0.06351802 = weight(_text_:system in 5129) [ClassicSimilarity], result of:
          0.06351802 = score(doc=5129,freq=8.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.5567675 = fieldWeight in 5129, product of:
              2.828427 = tf(freq=8.0), with freq of:
                8.0 = termFreq=8.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.0625 = fieldNorm(doc=5129)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    States that it can be shown that claims of a lack of theories of citation are also indicative of a great need for a theory which links science dynamics and measurement. There is a wide gap between qualitative (science dynamics) and quantitative (measurement) approaches. To link them, proposes the use of the citation system, that potentially bridges a gap between measurement and epistemology, by applying system theory to the publication system
  11. Hayer, L.: Lazarsfeld zitiert : eine bibliometrische Analyse (2008) 0.00 
    0.0017527144 = product of:
  0.0122690005 = sum of:
    0.0122690005 = product of:
      0.024538001 = sum of:
        0.024538001 = weight(_text_:22 in 1934) [ClassicSimilarity], result of:
          0.024538001 = score(doc=1934,freq=2.0), product of:
            0.12684377 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03622214 = queryNorm
            0.19345059 = fieldWeight in 1934, 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=1934)
      0.5 = coord(1/2)
  0.14285715 = coord(1/7)
    Date
    22. 6.2008 12:54:12
  12. Scharnhorst, A.: Citation - networks, science landscapes and evolutionary strategies (1998) 0.00 
    0.0013752056 = product of:
  0.009626439 = sum of:
    0.009626439 = product of:
      0.048132192 = sum of:
        0.048132192 = weight(_text_:system in 5126) [ClassicSimilarity], result of:
          0.048132192 = score(doc=5126,freq=6.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.42190298 = fieldWeight in 5126, product of:
              2.4494898 = tf(freq=6.0), with freq of:
                6.0 = termFreq=6.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.0546875 = fieldNorm(doc=5126)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    The construction of virtual science landscapes based on citation networks and the strategic use of the information therein shed new light on the issues of the evolution of the science system and possibilities for control. Leydesdorff's approach to citation theory described in his 1998 article (see this issue of LISA) takes into account the dual layered character of communication networks and the second order nature of the science system. This perspective may help to sharpen the awareness of scientists and science policy makers for possible feedback loops within actions and activities in the science system, and probably nonlinear phenomena resulting therefrom. Sketches an additional link to geometrically oriented evolutionary theories and uses a specific landscape concept as a framework for some comments
  13. Sidiropoulos, A.; Manolopoulos, Y.: ¬A new perspective to automatically rank scientific conferences using digital libraries (2005) 0.00 
    0.0013611005 = product of:
  0.009527703 = sum of:
    0.009527703 = product of:
      0.047638513 = sum of:
        0.047638513 = weight(_text_:system in 1011) [ClassicSimilarity], result of:
          0.047638513 = score(doc=1011,freq=8.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.41757566 = fieldWeight in 1011, product of:
              2.828427 = tf(freq=8.0), with freq of:
                8.0 = termFreq=8.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.046875 = fieldNorm(doc=1011)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    Citation analysis is performed in order to evaluate authors and scientific collections, such as journals and conference proceedings. Currently, two major systems exist that perform citation analysis: Science Citation Index (SCI) by the Institute for Scientific Information (ISI) and CiteSeer by the NEC Research Institute. The SCI, mostly a manual system up until recently, is based on the notion of the ISI Impact Factor, which has been used extensively for citation analysis purposes. On the other hand the CiteSeer system is an automatically built digital library using agents technology, also based on the notion of ISI Impact Factor. In this paper, we investigate new alternative notions besides the ISI impact factor, in order to provide a novel approach aiming at ranking scientific collections. Furthermore, we present a web-based system that has been built by extracting data from the Databases and Logic Programming (DBLP) website of the University of Trier. Our system, by using the new citation metrics, emerges as a useful tool for ranking scientific collections. In this respect, some first remarks are presented, e.g. on ranking conferences related to databases.
  14. Larsen, B.: Exploiting citation overlaps for information retrieval : generating a boomerang effect from the network of scientific papers (2002) 0.00 
    0.0012555057 = product of:
  0.00878854 = sum of:
    0.00878854 = product of:
      0.0439427 = sum of:
        0.0439427 = weight(_text_:retrieval in 4175) [ClassicSimilarity], result of:
          0.0439427 = score(doc=4175,freq=2.0), product of:
            0.109568894 = queryWeight, product of:
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.03622214 = queryNorm
            0.40105087 = fieldWeight in 4175, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.09375 = fieldNorm(doc=4175)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
  15. Cronin, B.: Semiotics and evaluative bibliometrics (2000) 0.00 
    0.0011342503 = product of:
  0.007939752 = sum of:
    0.007939752 = product of:
      0.03969876 = sum of:
        0.03969876 = weight(_text_:system in 4542) [ClassicSimilarity], result of:
          0.03969876 = score(doc=4542,freq=2.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.3479797 = fieldWeight in 4542, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.078125 = fieldNorm(doc=4542)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    The reciprocal relationship between bibliographic references and citations in the context of the scholarly communication system is examined. Semiotic analysis of referencing behaviours and citation counting reveals the complexity of prevailing sign systems and associated symbolic practices.
  16. Garfield, E.: From citation indexes to informetrics : is the tail now wagging the dog? (1998) 0.00 
    0.0010357393 = product of:
  0.007250175 = sum of:
    0.007250175 = product of:
      0.036250874 = sum of:
        0.036250874 = weight(_text_:retrieval in 2809) [ClassicSimilarity], result of:
          0.036250874 = score(doc=2809,freq=4.0), product of:
            0.109568894 = queryWeight, product of:
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.03622214 = queryNorm
            0.33085006 = fieldWeight in 2809, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.024915 = idf(docFreq=5836, maxDocs=44218)
              0.0546875 = fieldNorm(doc=2809)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    Provides a synoptic review and history of citation indexes and their evolution into research evaluation tools including a discussion of the use of bibliometric data for evaluating US institutions (academic departments) by the National Research Council (NRC). Covers the origin and uses of periodical impact factors, validation studies of citation analysis, information retrieval and dissemination (current awareness), citation consciousness, historiography and science mapping, Citation Classics, and the history of contemporary science. Illustrates the retrieval of information by cited reference searching, especially as it applies to avoiding duplicated research. Discusses the 15 year cumulative impacts of periodicals and the percentage of uncitedness, the emergence of scientometrics, old boy networks, and citation frequency distributions. Concludes with observations about the future of citation indexing
  17. Marx, W.: Wie mißt man Forschungsqualität? : der Science Citation Index - ein Maßstab für die Bewertung (1996) 0.00 
    9.0740033E-4 = product of:
  0.006351802 = sum of:
    0.006351802 = product of:
      0.03175901 = sum of:
        0.03175901 = weight(_text_:system in 5036) [ClassicSimilarity], result of:
          0.03175901 = score(doc=5036,freq=2.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.27838376 = fieldWeight in 5036, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.0625 = fieldNorm(doc=5036)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    Ein überfordertes Gutachter-System, knapper fließende Forschungsgelder sowie die starke Faszination von Ranglisten bewirken zunehmend den Einsatz bibliometrischer Methoden zur Messung von Forschungsqualität. Grundlage der meisten Bewertungen ist der Science Citation Index, der nun auch in der Version als Online-Datenbank für umfangreiche Analysen genutzt werden kann. Erweiterungen der Retrievalsprache beim Host STN International ermöglichen statistische Analysen, die bisher nur dem SCI-Hersteller und wenigen Spezialisten vorbehalten waren. Voraussetzung für eine sinnvolle Anwendung sind vor allem die Wahl geeigneter Selektionskriterien sowie die sorgfältige Interpretation der Ergebnisse im Rahmen der Grenzen dieser Methoden
  18. Wouters, P.: ¬The signs of science (1998) 0.00 
    9.0740033E-4 = product of:
  0.006351802 = sum of:
    0.006351802 = product of:
      0.03175901 = sum of:
        0.03175901 = weight(_text_:system in 1023) [ClassicSimilarity], result of:
          0.03175901 = score(doc=1023,freq=2.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.27838376 = fieldWeight in 1023, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.0625 = fieldNorm(doc=1023)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    Since the 'Science Citation Index' emerged within the system of scientific communication in 1964, an intense controversy about its character has been raging: in what sense can citation analysis be trusted? This debate can be characterized as the confrontation of different perspectives on science. Discusses the citation representation of science: the way the citation creates a new reality of as well as in the world of science; the main features of this reality; and some implications for science and science policy
  19. Moed, H.F.; Leeuwen, T.N. van; Reedijk, J.: ¬A new classification system to describe the ageing of scientific journals and their impact factors (1998) 0.00 
    9.0740033E-4 = product of:
  0.006351802 = sum of:
    0.006351802 = product of:
      0.03175901 = sum of:
        0.03175901 = weight(_text_:system in 4719) [ClassicSimilarity], result of:
          0.03175901 = score(doc=4719,freq=8.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.27838376 = fieldWeight in 4719, product of:
              2.828427 = tf(freq=8.0), with freq of:
                8.0 = termFreq=8.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03125 = fieldNorm(doc=4719)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    During the past decades, journal impact data obtained from the Journal Citation Reports (JCR) have gained relevance in library management, research management and research evaluation. Hence, both information scientists and bibliometricians share the responsibility towards the users of the JCR to analyse the reliability and validity of its measures thoroughly, to indicate pitfalls and to suggest possible improvements. In this article, ageing patterns are examined in 'formal' use or impact of all scientific journals processed for the Science Citation Index (SCI) during 1981-1995. A new classification system of journals in terms of their ageing characteristics is introduced. This system has been applied to as many as 3,098 journals covered by the Science Citation Index. Following an earlier suggestion by Glnzel and Schoepflin, a maturing and a decline phase are distinguished. From an analysis across all subfields it has been concluded that ageing characteristics are primarily specific to the individual journal rather than to the subfield, while the distribution of journals in terms of slowly or rapidly maturing or declining types is specific to the subfield. It is shown that the cited half life (CHL), printed in the JCR, is an inappropriate measure of decline of journal impact. Following earlier work by Line and others, a more adequate parameter of decline is calculated taking into account the size of annual volumes during a range of fifteen years. For 76 per cent of SCI journals the relative difference between this new parameter and the ISI CHL exceeds 5 per cent. The current JCR journal impact factor is proven to be biased towards journals revealing a rapid maturing and decline in impact. Therefore, a longer term impact factor is proposed, as well as a normalised impact statistic, taking into account citation characteristics of the research subfield covered by a journal and the type of documents published in it. When these new measures are combined with the proposed ageing classification system, they provide a significantly improved picture of a journal's impact to that obtained from the JCR.
  20. Kurtz, M.J.; Eichhorn, G.; Accomazzi, A.; Grant, C.; Demleitner, M.; Henneken, E.; Murray, S.S.: ¬The effect of use and access on citations (2005) 0.00 
    9.0740033E-4 = product of:
  0.006351802 = sum of:
    0.006351802 = product of:
      0.03175901 = sum of:
        0.03175901 = weight(_text_:system in 1064) [ClassicSimilarity], result of:
          0.03175901 = score(doc=1064,freq=2.0), product of:
            0.11408355 = queryWeight, product of:
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.03622214 = queryNorm
            0.27838376 = fieldWeight in 1064, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.1495528 = idf(docFreq=5152, maxDocs=44218)
              0.0625 = fieldNorm(doc=1064)
      0.2 = coord(1/5)
  0.14285715 = coord(1/7)
    Abstract
    It has been shown (Lawrence, S. (2001). Online or invisible? Nature, 411, 521) that journal articles which have been posted without charge on the internet are more heavily cited than those which have not been. Using data from the NASA Astrophysics Data System (ads.harvard.edu) and from the ArXiv e-print archive at Cornell University (arXiv.org) we examine the causes of this effect.

Authors

Years

Languages

  • e 27
  • d 3

Types

  • a 29
  • el 1
  • m 1
  • More… Less…

Themes