By Robin O’Hanlon, MIS

Dr. Gali Halevi, MLS, PhD recently has an article entitled “A new methodology for comparing Google Scholar and Scopus” published in Journal of Informetrics. Dr. Halevi published this article with two co-authors, Dr. Henk F. Moed, PhD (Senior Scientific Advisor, Elsevier) and Dr. Judit Bar-Ilan, PhD (Professor, Bar Ilan University).

In the article, a new methodology is proposed for comparing Google Scholar (GS) with other citation indexes. Article highlights include:

  • A new methodology is proposed for comparing Google Scholar (GS) with Scopus, focusing on indexing speed and duplicate citation counts.
  • The ratio of GS over Scopus citation varies across subject fields between 1.0 and 4.0, and is for Open Access journals higher than for other journals.
  • The linear correlation between GS and Scopus citation counts at the article level is high: Pearson’s R is in the range of 0.8–0.9.
  • A median Scopus indexing delay of two months compared to GS is largely due to missing cited references in articles in press in Scopus.
  • Double citation counts in GS due to multiple versions of the same document occurs in less than 2% of cases.

Fig. 1 Process of data collection per journal.

The article can be read in its entirety here (subscription fees apply) – http://goo.gl/82s2TS

Citation:

Moed, H. F., Bar-Ilan, J., & Halevi, G. (2016). A new methodology for comparing google scholar and scopus. Journal of Informetrics, 10(2), 533-551. doi:http://dx.doi.org/10.1016/j.joi.2016.04.017