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Other than detecting impact in advance, alternative metrics could act as early warning signs of retractions: tentative findings of a study into the papers retracted by PLoS ONE

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  • Sergio Copiello

    (IUAV University of Venice)

Abstract

The so-called altmetrics—short for alternative metrics—have gained their place in the scholarly publishing landscape, especially providing article-level complementary measures. But what do they point to? A hypothesis has found its way into the recent literature: they could be an early sign of impact, conveying in advance the information carried later by citations. Here the focus is on another possible relationship, namely, the one that may exist between alternative metrics and retractions. The research question is as follows: in comparison to non-retracted, contemporary publications, are the retracted articles likely to be more (or less) viewed and commented (but also «tweeted» and «blogged») before the retraction takes place? The above relationship is tested on a set of n = 209 papers retracted by PLoS ONE and a control group including 2n = 418 contemporary, non-retracted articles featured in the same journal. Significant and positive differences in means are found concerning the mentions in peer review sites and the number of views and downloads. On the whole, by considering five alternative metrics, about one-fourth of the retractions are predicted correctly.

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  • Sergio Copiello, 2020. "Other than detecting impact in advance, alternative metrics could act as early warning signs of retractions: tentative findings of a study into the papers retracted by PLoS ONE," Scientometrics, Springer;Akadémiai Kiadó, vol. 125(3), pages 2449-2469, December.
  • Handle: RePEc:spr:scient:v:125:y:2020:i:3:d:10.1007_s11192-020-03698-w
    DOI: 10.1007/s11192-020-03698-w
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    as
    1. Xianwen Wang & Zhi Wang & Shenmeng Xu, 2013. "Tracing scientist’s research trends realtimely," Scientometrics, Springer;Akadémiai Kiadó, vol. 95(2), pages 717-729, May.
    2. Robin Haunschild & Lutz Bornmann, 2018. "Field- and time-normalization of data with many zeros: an empirical analysis using citation and Twitter data," Scientometrics, Springer;Akadémiai Kiadó, vol. 116(2), pages 997-1012, August.
    3. Christian Pieter Hoffmann & Christoph Lutz & Miriam Meckel, 2016. "A relational altmetric? Network centrality on ResearchGate as an indicator of scientific impact," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 67(4), pages 765-775, April.
    4. Lutz Bornmann & Robin Haunschild, 2018. "Allegation of scientific misconduct increases Twitter attention," Scientometrics, Springer;Akadémiai Kiadó, vol. 115(2), pages 1097-1100, May.
    5. José Luis Ortega, 2018. "Reliability and accuracy of altmetric providers: a comparison among Altmetric.com, PlumX and Crossref Event Data," Scientometrics, Springer;Akadémiai Kiadó, vol. 116(3), pages 2123-2138, September.
    6. Johan Bollen & Herbert Van de Sompel & Aric Hagberg & Ryan Chute, 2009. "A Principal Component Analysis of 39 Scientific Impact Measures," PLOS ONE, Public Library of Science, vol. 4(6), pages 1-11, June.
    7. Zhichao Fang & Rodrigo Costas, 2020. "Studying the accumulation velocity of altmetric data tracked by Altmetric.com," Scientometrics, Springer;Akadémiai Kiadó, vol. 123(2), pages 1077-1101, May.
    8. Cameron Neylon & Shirley Wu, 2009. "Article-Level Metrics and the Evolution of Scientific Impact," PLOS Biology, Public Library of Science, vol. 7(11), pages 1-6, November.
    9. Christian Gumpenberger & Wolfgang Glänzel & Juan Gorraiz, 2016. "The ecstasy and the agony of the altmetric score," Scientometrics, Springer;Akadémiai Kiadó, vol. 108(2), pages 977-982, August.
    10. Andrea Giovanni Nuzzolese & Paolo Ciancarini & Aldo Gangemi & Silvio Peroni & Francesco Poggi & Valentina Presutti, 2019. "Do altmetrics work for assessing research quality?," Scientometrics, Springer;Akadémiai Kiadó, vol. 118(2), pages 539-562, February.
    11. Mike Thelwall & Paul Wilson, 2016. "Mendeley readership altmetrics for medical articles: An analysis of 45 fields," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 67(8), pages 1962-1972, August.
    12. Christine Meschede & Tobias Siebenlist, 2018. "Cross-metric compatability and inconsistencies of altmetrics," Scientometrics, Springer;Akadémiai Kiadó, vol. 115(1), pages 283-297, April.
    13. Mike Thelwall, 2017. "Are Mendeley reader counts useful impact indicators in all fields?," Scientometrics, Springer;Akadémiai Kiadó, vol. 113(3), pages 1721-1731, December.
    14. Xuemei Li & Mike Thelwall & Dean Giustini, 2012. "Validating online reference managers for scholarly impact measurement," Scientometrics, Springer;Akadémiai Kiadó, vol. 91(2), pages 461-471, May.
    15. Cassidy R. Sugimoto & Sam Work & Vincent Larivière & Stefanie Haustein, 2017. "Scholarly use of social media and altmetrics: A review of the literature," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 68(9), pages 2037-2062, September.
    16. Pardeep Sud & Mike Thelwall, 2014. "Evaluating altmetrics," Scientometrics, Springer;Akadémiai Kiadó, vol. 98(2), pages 1131-1143, February.
    17. Stefanie Haustein & Isabella Peters & Judit Bar-Ilan & Jason Priem & Hadas Shema & Jens Terliesner, 2014. "Coverage and adoption of altmetrics sources in the bibliometric community," Scientometrics, Springer;Akadémiai Kiadó, vol. 101(2), pages 1145-1163, November.
    18. Rafael Repiso & Antonio Castillo-Esparcia & Daniel Torres-Salinas, 2019. "Altmetrics, alternative indicators for Web of Science Communication studies journals," Scientometrics, Springer;Akadémiai Kiadó, vol. 119(2), pages 941-958, May.
    19. Zohreh Zahedi & Rodrigo Costas & Paul Wouters, 2014. "How well developed are altmetrics? A cross-disciplinary analysis of the presence of ‘alternative metrics’ in scientific publications," Scientometrics, Springer;Akadémiai Kiadó, vol. 101(2), pages 1491-1513, November.
    20. Mike Thelwall, 2018. "Early Mendeley readers correlate with later citation counts," Scientometrics, Springer;Akadémiai Kiadó, vol. 115(3), pages 1231-1240, June.
    21. Wolfgang Glänzel & Juan Gorraiz, 2015. "Usage metrics versus altmetrics: confusing terminology?," Scientometrics, Springer;Akadémiai Kiadó, vol. 102(3), pages 2161-2164, March.
    22. Christian Schlögl & Juan Gorraiz & Christian Gumpenberger & Kris Jack & Peter Kraker, 2014. "Comparison of downloads, citations and readership data for two information systems journals," Scientometrics, Springer;Akadémiai Kiadó, vol. 101(2), pages 1113-1128, November.
    23. Stefanie Haustein & Timothy D. Bowman & Kim Holmberg & Andrew Tsou & Cassidy R. Sugimoto & Vincent Larivière, 2016. "Tweets as impact indicators: Examining the implications of automated “bot” accounts on Twitter," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 67(1), pages 232-238, January.
    24. J. C. F. Winter, 2015. "The relationship between tweets, citations, and article views for PLOS ONE articles," Scientometrics, Springer;Akadémiai Kiadó, vol. 102(2), pages 1773-1779, February.
    25. Ortega, José Luis, 2015. "Relationship between altmetric and bibliometric indicators across academic social sites: The case of CSIC's members," Journal of Informetrics, Elsevier, vol. 9(1), pages 39-49.
    26. Martín-Martín, Alberto & Orduna-Malea, Enrique & Delgado López-Cózar, Emilio, 2018. "Author-level metrics in the new academic profile platforms: The online behaviour of the Bibliometrics community," Journal of Informetrics, Elsevier, vol. 12(2), pages 494-509.
    27. Tim Brody & Stevan Harnad & Leslie Carr, 2006. "Earlier Web usage statistics as predictors of later citation impact," Journal of the American Society for Information Science and Technology, Association for Information Science & Technology, vol. 57(8), pages 1060-1072, June.
    28. Zohreh Zahedi & Rodrigo Costas & Paul Wouters, 2017. "Mendeley readership as a filtering tool to identify highly cited publications," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 68(10), pages 2511-2521, October.
    29. Bornmann, Lutz, 2014. "Do altmetrics point to the broader impact of research? An overview of benefits and disadvantages of altmetrics," Journal of Informetrics, Elsevier, vol. 8(4), pages 895-903.
    30. Enrique Orduna-Malea & Alberto Martín-Martín & Mike Thelwall & Emilio Delgado López-Cózar, 2017. "Do ResearchGate Scores create ghost academic reputations?," Scientometrics, Springer;Akadémiai Kiadó, vol. 112(1), pages 443-460, July.
    31. Waltman, Ludo, 2016. "A review of the literature on citation impact indicators," Journal of Informetrics, Elsevier, vol. 10(2), pages 365-391.
    32. Bornmann, Lutz & Haunschild, Robin & Adams, Jonathan, 2019. "Do altmetrics assess societal impact in a comparable way to case studies? An empirical test of the convergent validity of altmetrics based on data from the UK research excellence framework (REF)," Journal of Informetrics, Elsevier, vol. 13(1), pages 325-340.
    33. Bornmann, Lutz & Haunschild, Robin, 2018. "Normalization of zero-inflated data: An empirical analysis of a new indicator family and its use with altmetrics data," Journal of Informetrics, Elsevier, vol. 12(3), pages 998-1011.
    34. José Luis Ortega, 2020. "Blogs and news sources coverage in altmetrics data providers: a comparative analysis by country, language, and subject," Scientometrics, Springer;Akadémiai Kiadó, vol. 122(1), pages 555-572, January.
    35. Pooladian, Aida & Borrego, Ángel, 2016. "A longitudinal study of the bookmarking of library and information science literature in Mendeley," Journal of Informetrics, Elsevier, vol. 10(4), pages 1135-1142.
    36. Haustein, Stefanie & Siebenlist, Tobias, 2011. "Applying social bookmarking data to evaluate journal usage," Journal of Informetrics, Elsevier, vol. 5(3), pages 446-457.
    37. Sergio Copiello, 2019. "Research Interest: another undisclosed (and redundant) algorithm by ResearchGate," Scientometrics, Springer;Akadémiai Kiadó, vol. 120(1), pages 351-360, July.
    38. Atanu Sengupta & Sanjoy De, 2020. "Review of Literature," India Studies in Business and Economics, in: Assessing Performance of Banks in India Fifty Years After Nationalization, chapter 0, pages 15-30, Springer.
    39. Adam Marcus & Ivan Oransky, 2011. "The paper is not sacred," Nature, Nature, vol. 480(7378), pages 449-450, December.
    40. McCabe Mark J & Snyder Christopher M., 2007. "Academic Journal Prices in a Digital Age: A Two-Sided Market Model," The B.E. Journal of Economic Analysis & Policy, De Gruyter, vol. 7(1), pages 1-39, January.
    41. Ortega, José Luis, 2018. "The life cycle of altmetric impact: A longitudinal study of six metrics from PlumX," Journal of Informetrics, Elsevier, vol. 12(3), pages 579-589.
    42. Sergio Copiello, 2020. "Multi-criteria altmetric scores are likely to be redundant with respect to a subset of the underlying information," Scientometrics, Springer;Akadémiai Kiadó, vol. 124(1), pages 819-824, July.
    43. Lutz Bornmann & Robin Haunschild, 2018. "Do altmetrics correlate with the quality of papers? A large-scale empirical study based on F1000Prime data," PLOS ONE, Public Library of Science, vol. 13(5), pages 1-12, May.
    44. Ludo Waltman & Rodrigo Costas, 2014. "F1000 Recommendations as a Potential New Data Source for Research Evaluation: A Comparison With Citations," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 65(3), pages 433-445, March.
    45. Frederique Bordignon, 2020. "Self-correction of science: a comparative study of negative citations and post-publication peer review," Scientometrics, Springer;Akadémiai Kiadó, vol. 124(2), pages 1225-1239, August.
    46. Gualberto Buela-Casal & Izabela Zych, 2012. "What do the scientists think about the impact factor?," Scientometrics, Springer;Akadémiai Kiadó, vol. 92(2), pages 281-292, August.
    47. Thelwall, Mike & Nevill, Tamara, 2018. "Could scientists use Altmetric.com scores to predict longer term citation counts?," Journal of Informetrics, Elsevier, vol. 12(1), pages 237-248.
    48. Nabeil Maflahi & Mike Thelwall, 2018. "How quickly do publications get read? The evolution of mendeley reader counts for new articles," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 69(1), pages 158-167, January.
    49. Wei Chen & Qin-Rui Xing & Hui Wang & Tao Wang, 2018. "Retracted publications in the biomedical literature with authors from mainland China," Scientometrics, Springer;Akadémiai Kiadó, vol. 114(1), pages 217-227, January.
    50. Mojisola Erdt & Aarthy Nagarajan & Sei-Ching Joanna Sin & Yin-Leng Theng, 2016. "Altmetrics: an analysis of the state-of-the-art in measuring research impact on social media," Scientometrics, Springer;Akadémiai Kiadó, vol. 109(2), pages 1117-1166, November.
    51. Furman, Jeffrey L. & Jensen, Kyle & Murray, Fiona, 2012. "Governing knowledge in the scientific community: Exploring the role of retractions in biomedicine," Research Policy, Elsevier, vol. 41(2), pages 276-290.
    52. Ehsan Mohammadi & Mike Thelwall, 2014. "Mendeley readership altmetrics for the social sciences and humanities: Research evaluation and knowledge flows," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 65(8), pages 1627-1638, August.
    53. Lutz Bornmann & Robin Haunschild, 2017. "Does evaluative scientometrics lose its main focus on scientific quality by the new orientation towards societal impact?," Scientometrics, Springer;Akadémiai Kiadó, vol. 110(2), pages 937-943, February.
    54. Richard Van Noorden, 2014. "Online collaboration: Scientists and the social network," Nature, Nature, vol. 512(7513), pages 126-129, August.
    55. Lutz Bornmann, 2015. "Alternative metrics in scientometrics: a meta-analysis of research into three altmetrics," Scientometrics, Springer;Akadémiai Kiadó, vol. 103(3), pages 1123-1144, June.
    56. Rodrigo Costas & Zohreh Zahedi & Paul Wouters, 2015. "Do “altmetrics” correlate with citations? Extensive comparison of altmetric indicators with citations from a multidisciplinary perspective," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 66(10), pages 2003-2019, October.
    57. Judit Bar-Ilan & Gali Halevi, 2018. "Temporal characteristics of retracted articles," Scientometrics, Springer;Akadémiai Kiadó, vol. 116(3), pages 1771-1783, September.
    58. Björn Hammarfelt, 2014. "Using altmetrics for assessing research impact in the humanities," Scientometrics, Springer;Akadémiai Kiadó, vol. 101(2), pages 1419-1430, November.
    59. Sebastian Vogl & Thomas Scherndl & Anton Kühberger, 2018. "#Psychology: a bibliometric analysis of psychological literature in the online media," Scientometrics, Springer;Akadémiai Kiadó, vol. 115(3), pages 1253-1269, June.
    60. Sergio Copiello & Pietro Bonifaci, 2018. "A few remarks on ResearchGate score and academic reputation," Scientometrics, Springer;Akadémiai Kiadó, vol. 114(1), pages 301-306, January.
    61. Anwar Said & Timothy D. Bowman & Rabeeh Ayaz Abbasi & Naif Radi Aljohani & Saeed-Ul Hassan & Raheel Nawaz, 2019. "Mining network-level properties of Twitter altmetrics data," Scientometrics, Springer;Akadémiai Kiadó, vol. 120(1), pages 217-235, July.
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