Search (9 results, page 1 of 1)

  • × author_ss:"Eck, N.J. van"
  • × theme_ss:"Informetrie"
  1. Olensky, M.; Schmidt, M.; Eck, N.J. van: Evaluation of the citation matching algorithms of CWTS and iFQ in comparison to the Web of science (2016) 0.01
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    Abstract
    The results of bibliometric studies provided by bibliometric research groups, for example, the Centre for Science and Technology Studies (CWTS) and the Institute for Research Information and Quality Assurance (iFQ), are often used in the process of research assessment. Their databases use Web of Science (WoS) citation data, which they match according to their own matching algorithms-in the case of CWTS for standard usage in their studies and in the case of iFQ on an experimental basis. Because the problem of nonmatched citations in the WoS persists due to inaccuracies in the references or inaccuracies introduced in the data extraction process, it is important to ascertain how well these inaccuracies are rectified in these citation matching algorithms. This article evaluates the algorithms of CWTS and iFQ in comparison to the WoS in a quantitative and a qualitative analysis. The analysis builds upon the method and the manually verified corpus of a previous study. The algorithm of CWTS performs best, closely followed by that of iFQ. The WoS algorithm still performs quite well (F1 score: 96.41%), but shows deficits in matching references containing inaccuracies. An additional problem is posed by incorrectly provided cited reference information in source articles by the WoS.
    Object
    Web of science
    Source
    Journal of the Association for Information Science and Technology. 67(2016) no.10, S.2550-2564
  2. Waltman, L.; Eck, N.J. van: ¬The inconsistency of the h-index : the case of web accessibility in Western European countries (2012) 0.00
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    Source
    Journal of the American Society for Information Science and Technology. 63(2012) no.2, S.406-415
  3. Colavizza, G.; Boyack, K.W.; Eck, N.J. van; Waltman, L.: ¬The closer the better : similarity of publication pairs at different cocitation levels (2018) 0.00
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    Abstract
    We investigated the similarities of pairs of articles that are cocited at the different cocitation levels of the journal, article, section, paragraph, sentence, and bracket. Our results indicate that textual similarity, intellectual overlap (shared references), author overlap (shared authors), proximity in publication time all rise monotonically as the cocitation level gets lower (from journal to bracket). While the main gain in similarity happens when moving from journal to article cocitation, all level changes entail an increase in similarity, especially section to paragraph and paragraph to sentence/bracket levels. We compared the results from four journals over the years 2010-2015: Cell, the European Journal of Operational Research, Physics Letters B, and Research Policy, with consistent general outcomes and some interesting differences. Our findings motivate the use of granular cocitation information as defined by meaningful units of text, with implications for, among others, the elaboration of maps of science and the retrieval of scholarly literature.
    Source
    Journal of the Association for Information Science and Technology. 69(2018) no.4, S.600-609
  4. Waltman, L.; Eck, N.J. van: ¬A new methodology for constructing a publication-level classification system of science : keyword maps in Google scholar citations (2012) 0.00
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    Abstract
    Classifying journals or publications into research areas is an essential element of many bibliometric analyses. Classification usually takes place at the level of journals, where the Web of Science subject categories are the most popular classification system. However, journal-level classification systems have two important limitations: They offer only a limited amount of detail, and they have difficulties with multidisciplinary journals. To avoid these limitations, we introduce a new methodology for constructing classification systems at the level of individual publications. In the proposed methodology, publications are clustered into research areas based on citation relations. The methodology is able to deal with very large numbers of publications. We present an application in which a classification system is produced that includes almost 10 million publications. Based on an extensive analysis of this classification system, we discuss the strengths and the limitations of the proposed methodology. Important strengths are the transparency and relative simplicity of the methodology and its fairly modest computing and memory requirements. The main limitation of the methodology is its exclusive reliance on direct citation relations between publications. The accuracy of the methodology can probably be increased by also taking into account other types of relations-for instance, based on bibliographic coupling.
    Source
    Journal of the American Society for Information Science and Technology. 63(2012) no.12, S.2378-2392
  5. Eck, N.J. van; Waltman, L.: Appropriate similarity measures for author co-citation analysis (2008) 0.00
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    Source
    Journal of the American Society for Information Science and Technology. 59(2008) no.10, S.1653-1661
  6. Waltman, L.; Eck, N.J. van: ¬The relation between eigenfactor, audience factor, and influence weight (2010) 0.00
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    Source
    Journal of the American Society for Information Science and Technology. 61(2010) no.7, S.1476-1486
  7. Waltman, L.; Eck, N.J. van; Raan, A.F.J. van: Universality of citation distributions revisited (2012) 0.00
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    Source
    Journal of the American Society for Information Science and Technology. 63(2012) no.1, S.72-77
  8. Eck, N.J. van; Waltman, L.; Dekker, R.; Berg, J. van den: ¬A comparison of two techniques for bibliometric mapping : multidimensional scaling and VOS (2010) 0.00
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    Source
    Journal of the American Society for Information Science and Technology. 61(2010) no.12, S.2405-2416
  9. Waltman, L.; Calero-Medina, C.; Kosten, J.; Noyons, E.C.M.; Tijssen, R.J.W.; Eck, N.J. van; Leeuwen, T.N. van; Raan, A.F.J. van; Visser, M.S.; Wouters, P.: ¬The Leiden ranking 2011/2012 : data collection, indicators, and interpretation (2012) 0.00
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    Source
    Journal of the American Society for Information Science and Technology. 63(2012) no.12, S.2405-2418