The application of currently available sophisticated algorithms of citation analysis allows for the incorporation of the "quality" of citations in the evaluation of scientific journals. We sought to compare the newly introduced SCImago journal rank (SJR) indicator with the journal impact factor (IF). We retrieved relevant information from the official Web sites hosting the above indices and their source databases. The SJR indicator is an open-access resource, while the journal IF requires paid subscription. The SJR indicator (based on Scopus data) lists considerably more journal titles published in a wider variety of countries and languages, than the journal IF (based on Web of Science data). Both indices divide citations to a journal by articles of the journal, during a specific time period. However, contrary to the journal IF, the SJR indicator attributes different weight to citations depending on the "prestige" of the citing journal without the influence of journal self-citations; prestige is estimated with the application of the PageRank algorithm in the network of journals. In addition, the SJR indicator includes the total number of documents of a journal in the denominator of the relevant calculation, whereas the journal IF includes only "citable" articles (mainly original articles and reviews). A 3-yr period is analyzed in both indices but with the use of different approaches. Regarding the top 100 journals in the 2006 journal IF ranking order, the median absolute change in their ranking position with the use of the SJR indicator is 32 (1st quartile: 12; 3rd quartile: 75). Although further validation is warranted, the novel SJR indicator poses as a serious alternative to the well-established journal IF, mainly due to its open-access nature, larger source database, and assessment of the quality of citations.
Posted by
Peter Suber at 4/17/2008 09:18:00 AM.
The open access movement:
Putting peer-reviewed scientific and scholarly literature
on the internet. Making it available free of charge and
free of most copyright and licensing restrictions.
Removing the barriers to serious research.
I recommend the OA tracking project (OATP) as the best way to stay on top of new OA developments. You can read the OATP feed on a blog-like web page or subscribe to it by RSS, email, or Twitter. You can also help build the feed by tagging new developments you encounter.
