Search (4 results, page 1 of 1)

  • × author_ss:"Leeuwen, T.N. van"
  • × author_ss:"Costas, R."
  1. Costas, R.; Bordons, M.; Leeuwen, T.N. van; Raan, A.F.J. van: Scaling rules in the science system : Influence of field-specific citation characteristics on the impact of individual researchers (2009) 0.03
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    Abstract
    The representation of science as a citation density landscape and the study of scaling rules with the field-specific citation density as a main topological property was previously analyzed at the level of research groups. Here, the focus is on the individual researcher. In this new analysis, the size dependence of several main bibliometric indicators for a large set of individual researchers is explored. Similar results as those previously observed for research groups are described for individual researchers. The total number of citations received by scientists increases in a cumulatively advantageous way as a function of size (in terms of number of publications) for researchers in three areas: Natural Resources, Biology & Biomedicine, and Materials Science. This effect is stronger for researchers in low citation density fields. Differences found among thematic areas with different citation densities are discussed.
    Date
    22. 3.2009 19:02:48
    Footnote
    Vgl. auch: Raan, A.F.J. van: Scaling rules in the science system: influence of field-specific citation characteristics on the impact of research groups. In: Journal of the American Society for Information Science and Technology. 59(2008) no.4, S.565-576.
  2. Costas, R.; Leeuwen, T.N. van; Bordons, M.: ¬A bibliometric classificatory approach for the study and assessment of research performance at the individual level : the effects of age on productivity and impact (2010) 0.01
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    Abstract
    The authors set forth a general methodology for conducting bibliometric analyses at the micro level. It combines several indicators grouped into three factors or dimensions, which characterize different aspects of scientific performance. Different profiles or classes of scientists are described according to their research performance in each dimension. A series of results based on the findings from the application of this methodology to the study of Spanish National Research Council scientists in Spain in three thematic areas are presented. Special emphasis is made on the identification and description of top scientists from structural and bibliometric perspectives. The effects of age on the productivity and impact of the different classes of scientists are analyzed. The classificatory approach proposed herein may prove a useful tool in support of research assessment at the individual level and for exploring potential determinants of research success.
  3. Costas, R.; Leeuwen, T.N. van; Bordons, M.: Referencing patterns of individual researchers : do top scientists rely on more extensive information sources? (2012) 0.01
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    Abstract
    This study presents an analysis of the use of bibliographic references by individual scientists in three different research areas. The number and type of references that scientists include in their papers are analyzed, the relationship between the number of references and different impact-based indicators is studied from a multivariable perspective, and the referencing patterns of scientists are related to individual factors such as their age and scientific performance. Our results show inter-area differences in the number, type, and age of references. Within each area, the number of references per document increases with journal impact factor and paper length. Top-performance scientists use in their papers a higher number of references, which are more recent and more frequently covered by the Web of Science. Veteran researchers tend to rely more on older literature and non-Web of Science sources. The longer reference lists of top scientists can be explained by their tendency to publish in high impact factor journals, with stricter reference and reviewing requirements. Long reference lists suggest a broader knowledge on the current literature in a field, which is important to become a top scientist. From the perspective of the "handicap principle theory," the sustained use of a high number of references in an author's oeuvre is a costly behavior that may indicate a serious, comprehensive, and solid research capacity, but that only the best researchers can afford. Boosting papers' citations by artificially increasing the number of references does not seem a feasible strategy.
  4. Costas, R.; Leeuwen, T.N. van: Approaching the "reward triangle" : general analysis of the presence of funding acknowledgments and "peer interactive communication" in scientific publications (2012) 0.00
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    Abstract
    Understanding the role of acknowledgments given by researchers in their publications has been a recurrent challenge in the bibliometric field, but relatively unexplored until now. This study presents a general bibliometric analysis on the new "funding acknowledgment" (FA) information available in the Web of Science. All publications covered by the database in 2009 have been analyzed. The presence and length of the FA text, as well as the presence of "peer interactive communication" in the acknowledgments, are related to impact indicators, distribution of papers by fields, countries of the authors, and collaboration level of the papers. It is observed that publications with FAs present a higher impact as compared with publications without them. There are also differences across countries and disciplines in the share of publications with FAs and the acknowledgment of peer interactive communication. China is the country with the highest share of publications acknowledging funding, while the presence of FAs in the humanities and social sciences is very low compared to the more basic disciplines. The presence of peer interactive communication in acknowledgments can be linked to countries that have a strong scientific tradition and are incorporated in scientific networks. Peer interactive communication is also common in the fields of humanities and social sciences and can be linked to lower levels of co-authorship. Observed patterns are explained and topics of future research are proposed.