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  • × author_ss:"Costas, R."
  1. Costas, R.; Perianes-Rodríguez, A.; Ruiz-Castillo, J.: On the quest for currencies of science : field "exchange rates" for citations and Mendeley readership (2017) 0.00 
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    Abstract
    Purpose The introduction of "altmetrics" as new tools to analyze scientific impact within the reward system of science has challenged the hegemony of citations as the predominant source for measuring scientific impact. Mendeley readership has been identified as one of the most important altmetric sources, with several features that are similar to citations. The purpose of this paper is to perform an in-depth analysis of the differences and similarities between the distributions of Mendeley readership and citations across fields. Design/methodology/approach The authors analyze two issues by using in each case a common analytical framework for both metrics: the shape of the distributions of readership and citations, and the field normalization problem generated by differences in citation and readership practices across fields. In the first issue the authors use the characteristic scores and scales method, and in the second the measurement framework introduced in Crespo et al. (2013). Findings There are three main results. First, the citations and Mendeley readership distributions exhibit a strikingly similar degree of skewness in all fields. Second, the results on "exchange rates (ERs)" for Mendeley readership empirically supports the possibility of comparing readership counts across fields, as well as the field normalization of readership distributions using ERs as normalization factors. Third, field normalization using field mean readerships as normalization factors leads to comparably good results. Originality/value These findings open up challenging new questions, particularly regarding the possibility of obtaining conflicting results from field normalized citation and Mendeley readership indicators; this suggests the need for better determining the role of the two metrics in capturing scientific recognition.
    Date
    20. 1.2015 18:30:22
  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) 0.00 
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    Source
    Journal of the American Society for Information Science and Technology. 61(2010) no.8, S.1564-1581
    Year
    2010
  3. 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) 0.00 
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    Source
    Journal of the American Society for Information Science and Technology. 61(2010) no.2, S.329-339
    Year
    2010
  4. Zahedi, Z.; Costas, R.; Wouters, P.: Mendeley readership as a filtering tool to identify highly cited publications (2017) 0.00 
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    Abstract
    This study presents a large-scale analysis of the distribution and presence of Mendeley readership scores over time and across disciplines. We study whether Mendeley readership scores (RS) can identify highly cited publications more effectively than journal citation scores (JCS). Web of Science (WoS) publications with digital object identifiers (DOIs) published during the period 2004-2013 and across five major scientific fields were analyzed. The main result of this study shows that RS are more effective (in terms of precision/recall values) than JCS to identify highly cited publications across all fields of science and publication years. The findings also show that 86.5% of all the publications are covered by Mendeley and have at least one reader. Also, the share of publications with Mendeley RS is increasing from 84% in 2004 to 89% in 2009, and decreasing from 88% in 2010 to 82% in 2013. However, it is noted that publications from 2010 onwards exhibit on average a higher density of readership versus citation scores. This indicates that compared to citation scores, RS are more prevalent for recent publications and hence they could work as an early indicator of research impact. These findings highlight the potential and value of Mendeley as a tool for scientometric purposes and particularly as a relevant tool to identify highly cited publications.
  5. 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) 0.00 
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    Date
    22. 3.2009 19:02:48
  6. Costas, R.; Zahedi, Z.; Wouters, P.: ¬The thematic orientation of publications mentioned on social media : large-scale disciplinary comparison of social media metrics with citations (2015) 0.00 
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    Date
    20. 1.2015 18:30:22

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