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  • × author_ss:"Costas, R."
  • × language_ss:"e"
  • × theme_ss:"Informetrie"
  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) 0.01
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    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.
    Source
    Journal of the American Society for Information Science and Technology. 60(2009) no.4, S.740-753
  2. Costas, R.; Perianes-Rodríguez, A.; Ruiz-Castillo, J.: On the quest for currencies of science : field "exchange rates" for citations and Mendeley readership (2017) 0.01
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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
    Footnote
    Beitrag eines Special issue on "The reward system of science".
    Source
    Aslib journal of information management. 69(2017) no.5, S.557-575
  3. Fang, Z.; Dudek, J.; Costas, R.: Facing the volatility of tweets in altmetric research (2022) 0.00
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    Abstract
    The data re-collection for tweets from data snapshots is a common methodological step in Twitter-based research. Understanding better the volatility of tweets over time is important for validating the reliability of metrics based on Twitter data. We tracked a set of 37,918 original scholarly tweets mentioning COVID-19-related research daily for 56 days and captured the reasons for the changes in their availability over time. Results show that the proportion of unavailable tweets increased from 1.6 to 2.6% in the time window observed. Of the 1,323 tweets that became unavailable at some point in the period observed, 30.5% became available again afterwards. "Revived" tweets resulted mainly from the unprotecting, reactivating, or unsuspending of users' accounts. Our findings highlight the importance of noting this dynamic nature of Twitter data in altmetric research and testify to the challenges that this poses for the retrieval, processing, and interpretation of Twitter data about scientific papers.
    Source
    Journal of the Association for Information Science and Technology. 73(2022) no.8, S.1192-1195
  4. 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
    Source
    Aslib journal of information management. 67(2015) no.3, S.260 - 288
  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) 0.00
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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.
    Source
    Journal of the American Society for Information Science and Technology. 63(2012) no.8, S.1647-1661
  6. Costas, R.; Leeuwen, T.N. van; Bordons, M.: Referencing patterns of individual researchers : do top scientists rely on more extensive information sources? (2012) 0.00
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    Source
    Journal of the American Society for Information Science and Technology. 63(2012) no.12, S.2433-2450
  7. Fang, Z.; Costas, R.; Tian, W.; Wang, X.; Wouters, P.: How is science clicked on Twitter? : click metrics for Bitly short links to scientific publications (2021) 0.00
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    Abstract
    To provide some context for the potential engagement behavior of Twitter users around science, this article investigates how Bitly short links to scientific publications embedded in scholarly Twitter mentions are clicked on Twitter. Based on the click metrics of over 1.1 million Bitly short links referring to Web of Science (WoS) publications, our results show that around 49.5% of them were not clicked by Twitter users. For those Bitly short links with clicks from Twitter, the majority of their Twitter clicks accumulated within a short period of time after they were first tweeted. Bitly short links to the publications in the field of Social Sciences and Humanities tend to attract more clicks from Twitter over other subject fields. This article also assesses the extent to which Twitter clicks are correlated with some other impact indicators. Twitter clicks are weakly correlated with scholarly impact indicators (WoS citations and Mendeley readers), but moderately correlated to other Twitter engagement indicators (total retweets and total likes). In light of these results, we highlight the importance of paying more attention to the click metrics of URLs in scholarly Twitter mentions, to improve our understanding about the more effective dissemination and reception of science information on Twitter.
    Source
    Journal of the Association for Information Science and Technology. 72(2021) no.7, S.918-932
  8. 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
  9. Waltman, L.; Costas, R.: F1000 Recommendations as a potential new data source for research evaluation : a comparison with citations (2014) 0.00
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    Source
    Journal of the Association for Information Science and Technology. 65(2014) no.3, S.433-445
  10. 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
  11. Costas, R.; Zahedi, Z.; Wouters, P.: Do "altmetrics" correlate with citations? : extensive comparison of altmetric indicators with citations from a multidisciplinary perspective (2015) 0.00
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    Source
    Journal of the Association for Information Science and Technology. 66(2015) no.10, S.2003-2019
  12. Schneider, J.W.; Costas, R.: Identifying potential "breakthrough" publications using refined citation analyses : three related explorative approaches (2017) 0.00
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    Source
    Journal of the Association for Information Science and Technology. 68(2017) no.3, S.709-723
  13. Zahedi, Z.; Costas, R.; Wouters, P.: Mendeley readership as a filtering tool to identify highly cited publications (2017) 0.00
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    Source
    Journal of the Association for Information Science and Technology. 68(2017) no.10, S.2511-2521
  14. Costas, R.; Rijcke, S. de; Marres, N.: "Heterogeneous couplings" : operationalizing network perspectives to study science-society interactions through social media metrics (2021) 0.00
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    Source
    Journal of the Association for Information Science and Technology. 72(2021) no.5, S.595-610