Abstract
In November 2012 the Google Scholar Metrics (GSM) journal rankings were updated, making it possible to compare bibliometric indicators in the ten languages indexed—and their stability—with the April 2012 version. The h-index and h-5 median of 1,000 journals were analysed, comparing their averages, maximum and minimum values and the correlation coefficient within rankings. The bibliometric figures grew significantly. In just seven and a half months the h-index of the journals increased by 15 % and the median h-index by 17 %. This growth was observed for all the bibliometric indicators analysed and for practically every journal. However, we found significant differences in growth rates depending on the language in which the journal is published. Moreover, the journal rankings seem to be stable between April and November, reinforcing the credibility of the data held by Google Scholar and the reliability of the GSM journal rankings, despite the uncontrolled growth of Google Scholar. Based on the findings of this study we suggest, firstly, that Google should upgrade its rankings at least semi-annually and, secondly, that the results should be displayed in each ranking proportionally to the number of journals indexed by language.
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Notes
Google Scholar Metrics, http://scholar.google.com/citations?view_op=top_venues&hl=en (Accessed 1 September 2013).
http://googlescholar.blogspot.com.es/2012/04/googlescholar-metrics-for-publications.html (Accessed 1 September 2013).
http://scholar.google.com/intl/en/scholar/metrics.html (Accessed 1 September 2013).
In July 2013 the third version of GSM appeared, in which the citation window varied (2008–2012). For this reason this version is not taken into account in this longitudinal study. More information: http://arxiv.org/ftp/arxiv/papers/1307/1307.6941.pdf (Accessed 1 September 2013).
http://scholar.google.com/intl/en/scholar/metrics.html#metrics (Accessed 1 September 2013).
The raw data for the two GSM editions are available in Annex I of the supplementary material. http://hdl.handle.net/10481/28290 (Accessed 8 October 2013).
The raw data for the weekly analysis of coverage in GS, Scopus and WoS are available in Annex II of the supplementary material. http://hdl.handle.net/10481/28290 (Accessed 8 October 2013).
References
Aguillo, & Isidro, F. (2012). Is Google Scholar useful for bibliometrics? A webometric analysis. Scientometrics, 91(2), 343–351.
Brewington, B. E., & Cybenko, G. (2000). How dynamic is the Web? Computer Networks, 33(1–6), 257–276.
Chen, X. (2010). Google Scholar’s dramatic coverage improvement five years after debut. Serials Review, 36(4), 221–226.
Cho, Y. & Garcia-Molina, H. (2000). The evolution of the web and implications for an incremental crawler. Proceedings of the 26th International Conference on very large data bases, 200–209.
Costas, R., & Bordons, M. (2007). The h-index: advantages, limitations and its relation with other bibliometric indicators at the micro level. Journal of Informetrics, 1(3), 193–203.
de Winter, J. C. F., Zadpoor, A. A., & Dodou, D. (2013). The expansion of Google Scholar versus Web of Science: a longitudinal study. Scientometrics. doi:10.1007/s11192-013-1089-2.
Delgado López-Cózar, E., & Cabezas-Clavijo, A. (2012). Google Scholar Metrics: an unreliable tool for assessing scientific journals. El profesional de la información, 21(4), 419–427.
Delgado López-Cózar, E., & Cabezas-Clavijo, A. (2013). Ranking journals: could Google Scholar metrics be an alternative to journal citation reports and Scimago journal ranks. Learned publishing, 26(2), 101–114.
Fetterly, D., Manasse, M., Najork, M. & Wiener, J. (2003). A large scale study of the evolution of web pages. Proceedings of the Twelfth International Conference on World Wide Web, 669–678.
Harzing, A.-W. (2013). A preliminary test of Google Scholar as a source for citation data: a longitudinal study of Nobel prize winners. Scientometrics, 94(3), 1057–1075.
Jacsó, P. (2012). Google Scholar Metrics for Publications—The software and content feature of a new open access bibliometric service. Online Information Review, 36(4), 604–619.
Koehler, W. (2002). Web page change and persistence-4-year longitudinal web study. Journal of the American Society for Information Science and Technology, 53(2), 162–171.
Koehler, W (2004). A longitudinal study of Web pages continued a consideration of document persistence. Information Research, 9(2). http://informationr.net/ir/9-2/paper174.html. Accessed 1 Sep 2013.
Kousha, K., & Thelwall, M. (2007). Google Scholar Citations and Google Web/URL citations: a multidiscipline exploratory analysis. Journal of the American Society for Information Science and Technology, 58(7), 1055–1065.
Leydesdorff, L. (2012). World shares of publications of the USA, EU-27, and China compared and predicted using the new Web of Science interface versus Scopus. El profesional de la información, 21(1), 43–49.
Neuhaus, C., Neuhaus, E., Asher, A., & Wrede, C. (2006). The depth and breadth of Google Scholar: An empirical study. Libraries and the Academy, 6(2), 127–141.
Orduña-Malea, E., Serrano-Cobos, J., & Lloret-Romero, N. (2009). Las universidades públicas españolas en Google Scholar: presencia y evolución de su publicación académica web. El profesional de la información, 18(5), 493–500.
Orduña-Malea, E., Serrano-Cobos, J., Ontalba-Ruipérez, J.-A., & Lloret-Romero, N. (2010). Presencia y visibilidad web de las universidades públicas españolas. Revista española de documentación científica, 33(2), 246–278.
Ortega, J. L., Aguillo, I. F., & Prieto, J. A. (2006). Longitudinal study of contents and elements in the scientific Web environment. Journal of Information Science, 32(4), 344–351.
Payne, N., & Thelwall, M. (2007). A longitudinal study of academic webs: growth and stabilization. Scientometrics, 71(3), 523–539.
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Orduña-Malea, E., Delgado López-Cózar, E. Google Scholar Metrics evolution: an analysis according to languages. Scientometrics 98, 2353–2367 (2014). https://doi.org/10.1007/s11192-013-1164-8
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DOI: https://doi.org/10.1007/s11192-013-1164-8
Keywords
- Google Scholar Metrics
- Google Scholar
- Scientific journals
- h-Index
- Journal rankings
- Bibliometric databases