Google Scholar Citations and Google Web/URL Citations: A Multi-Discipline Exploratory Analysis

In this paper we introduce a new data gathering method “Web/URL Citation” and use it and Google Scholar as a basis to compare traditional and Web-based citation patterns across multiple disciplines. For this, we built a sample of 1,650 articles from 108 Open Access (OA) journals published in 2001 in four science and four social science disciplines. We recorded the number of citations to the sample articles using several methods based upon the ISI Web of Science, Google Scholar and the Google search engine (Web/URL citations). For each discipline, we found significant correlations between ISI citations and both Google Scholar and Google Web/URL citations; with similar results when using total or average citations, and when comparing within and across (most) journals. We also investigated disciplinary differences. Google Scholar citations were more numerous than ISI citations in our four social science disciplines as well as in computer science, suggesting that Google Scholar is a more comprehensive tool for citation tracking in the social sciences and perhaps also in fast-moving fields where conference papers are highly valued and published online. The results for Web/URL citations suggested that counting a maximum of one hit per site produces a better measure for assessing the impact of OA journals or articles, because replicated web citations are very common within individual sites. The results can be considered as additional evidence that there is some commonality between traditional and Web-extracted citations