A preliminary test of Google Scholar as a source for citation data: a longitudinal study of Nobel prize winners
Most governmental research assessment exercises do not use citation data for the Social Sciences and Humanities as Web of Science or Scopus coverage in these disciplines is considered to be insufficient. We therefore assess to what extent Google Scholar can be used as an alternative source of citation data. In order to provide a credible alternative, Google Scholar needs to be stable over time, display comprehensive coverage, and provide non-biased comparisons across disciplines. This article assesses these conditions through a longitudinal study of 20 Nobel Prize winners in Chemistry, Economics, Medicine and Physics. Our results indicate that Google Scholar displays considerable stability over time. However, coverage for disciplines that have traditionally been poorly represented in Google Scholar (Chemistry and Physics) is increasing rapidly. Google Scholar’s coverage is also comprehensive; all of the 800 most cited publications by our Nobelists can be located in Google Scholar, although in four cases there are some problems with the results. Finally, we argue that Google Scholar might provide a less biased comparison across disciplines than the Web of Science. The use of Google Scholar might therefore redress the traditionally disadvantaged position of the Social Sciences in citation analysis.
KeywordsGoogle Scholar Web of science Social sciences Citation analysis
- Belew, R. K. (2005). Scientific impact quantity and quality: Analysis of two sources of bibliographic data, arXiv:cs.IR/0504036 v1, 11 April 2005.Google Scholar
- Bornmann, L., Marx, W., Schier, H., Rahm, E., Thor, A., & Daniel, H.-D. (2009). Convergent validity of bibliometric Google Scholar data in the field of chemistry: Citation counts for papers that were accepted by Angewandte Chemie International Edition or rejected but published elsewhere, using Google Scholar, Science Citation Index, Scopus, and Chemical Abstracts. Journal of Informetrics, 3(1), 27–35.CrossRefGoogle Scholar
- Bosman, J., Mourik, I. van, Rasch, M., Sieverts, E., & Verhoeff, H. (2006). Scopus reviewed and compared. The coverage and functionality of the citation database Scopus, including comparisons with Web of Science and Google Scholar, Utrecht: Utrecht University Library, http://igitur-archive.library.uu.nl/DARLIN/2006-1220-200432/Scopusdoorgelicht&vergelekentranslated.pdf.
- García-Pérez, M. A. (2010). Accuracy and completeness of publication and Citation Records in the Web of Science, PsycINFO, and Google Scholar: A case study for the computation of h indices in Psychology. Journal of the American Society for Information Science and Technology, 61(10), 2070–2085.CrossRefGoogle Scholar
- Hare, J. (2011). Most universities below par on research, The Australian, 1 February, 2011, http://www.theaustralian.com.au/higher-education/most-universities-below-par-on-research/story-e6frgcjx-1225997730868.
- Harzing, A. W. (2007). Publish or Perish. Retrieved from http://www.harzing.com/pop.htm.
- Harzing, A. W. (2010a). Citation analysis across disciplines: The Impact of different data sources and citation metrics, www.harzing.com white paper, Retrieved January 31, 2012, from http://www.harzing.com/data_metrics_comparison.htm.
- Harzing, A. W. (2010b). The Publish or Perish Book: Your guide to effective and responsible citation analysis. Melbourne: Tarma Software Research.Google Scholar
- Harzing, A. W., & van der Wal, R. (2008). Google Scholar as a new source for citation analysis? Ethics in Science and Environmental Politics, 8(1), 62–71.Google Scholar
- Jump, P. (2011). Free app has the cite stuff for REF, Times Higher Education Supplement. Retrieved June 30, 2011, from http://www.timeshighereducation.co.uk/story.asp?storycode=416647.
- London School of Economics and Political Science. (2011). Impact of the social sciences: Maximizing the impact of academic research. Retrieved from http://blogs.lse.ac.uk/impactofsocialsciences/.
- Murphy, P. (1996). Determining measures of the quality and impact of journals, Commissioned Report No. 49, Australian Government Publishing Service, Canberra.Google Scholar
- Pauly, D., & Stergiou, K. I. (2005). Equivalence of results from two citation analyses: Thomson ISI’s Citation Index and Google Scholar’s service (pp. 33–35). December: Ethics in Science and Environmental Politics.Google Scholar