Search (6 results, page 1 of 1)

  • × author_ss:"Leeuwen, T.N. van"
  • × year_i:[2010 TO 2020}
  1. 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.
  2. Calero Medina, C.M.; Leeuwen, T.N. van: Seed journal citation network maps : a method based on network theory (2012) 0.01
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    Abstract
    The study presented here shows a method based on network theory to identify the most important journals related to a given journal, the seed journal. In just one simple network map, we get the relevant citation environment of a specific seed journal. It is of interest to librarians, publishers, scientists and science policy makers. These journal citation network maps are useful for these various stakeholders in and around the science system, as they provide information on the level of journal connections, unlike the more traditional structures such as the Journal Subject Categories, the classification system applied in the products of Thomson Reuters (Journal Citation Reports, Web of Science, etc.). These network maps show the closest relations journals can have, based on citation relations, suggesting influence relations between journals in such a way that traditional field boundaries are transcended.
  3. Leeuwen, T.N. van; Tatum, C.; Wouters, P.F: Exploring possibilities to use bibliometric data to monitor gold open access publishing at the national level (2018) 0.01
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    Abstract
    This article1 describes the possibilities to analyze open access (OA) publishing in the Netherlands in an international comparative way. OA publishing is now actively stimulated by Dutch science policy, similar to the United Kingdom. We conducted a bibliometric baseline measurement to assess the current situation, to be able to measure developments over time. We collected data from various sources, and for three different smaller European countries (the Netherlands, Denmark, and Switzerland). Not all of the analyses for this baseline measurement are included here. The analysis presented in this article focuses on the various ways OA can be defined using the Web of Science, limiting the analysis mainly to Gold OA. From the data we collected we can conclude that the way OA is currently registered in various electronic bibliographic databases is quite unclear, and various methods applied deliver results that are different, although the impact scores derived from the data point in the same direction.
  4. Costas, R.; Leeuwen, T.N. van; Raan, A.F.J. van: Is scientific literature subject to a 'Sell-By-Date'? : a general methodology to analyze the 'durability' of scientific documents (2010) 0.01
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    Abstract
    The study of the citation histories and ageing of documents are topics that have been addressed from several perspectives, especially in the analysis of documents with delayed recognition or sleeping beauties. However, there is no general methodology that can be extensively applied for different time periods or research fields. In this article, a new methodology for the general analysis of the ageing and durability of scientific papers is presented. This methodology classifies documents into three general types: delayed documents, which receive the main part of their citations later than normal documents; flashes in the pan, which receive citations immediately after their publication but are not cited in the long term; and normal documents, documents with a typical distribution of citations over time. These three types of durability have been analyzed considering the whole population of documents in the Web of Science with at least 5 external citations (i.e., not considering self-citations). Several patterns related to the three types of durability have been found and the potential for further research of the developed methodology is discussed.
  5. 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) 0.01
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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.
  6. 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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    Abstract
    The Leiden Ranking 2011/2012 is a ranking of universities based on bibliometric indicators of publication output, citation impact, and scientific collaboration. The ranking includes 500 major universities from 41 different countries. This paper provides an extensive discussion of the Leiden Ranking 2011/2012. The ranking is compared with other global university rankings, in particular the Academic Ranking of World Universities (commonly known as the Shanghai Ranking) and the Times Higher Education World University Rankings. The comparison focuses on the methodological choices underlying the different rankings. Also, a detailed description is offered of the data collection methodology of the Leiden Ranking 2011/2012 and of the indicators used in the ranking. Various innovations in the Leiden Ranking 2011/2012 are presented. These innovations include (1) an indicator based on counting a university's highly cited publications, (2) indicators based on fractional rather than full counting of collaborative publications, (3) the possibility of excluding non-English language publications, and (4) the use of stability intervals. Finally, some comments are made on the interpretation of the ranking and a number of limitations of the ranking are pointed out.