Evaluation based on scientific publishing: SCImago Journal Rank indicator, SJR

SCImago Journal Rank indicator, SJR

SCImago is a research group from the Consejo Superior de Investigaciones Científicas (CSIC), University of Granada, Extremadura, Carlos III (Madrid) and Alcalá de Henares, dedicated to information analysis, representation and retrieval by means of visualisation techniques. The group has developed the SJR Portal and the SCImago Journal Rank (SJR) indicator.

The SJR indicator is a size-independent metric aimed at measuring the current average prestige per paper of journals. A citation from a journal with a relatively high SJR is worth more than a citation from a journal with a lower SJR.

The SJR scores for journals are available at http://www.scimagojr.com/. Scopus Journal Analyzer publishes SJR values for journals from 1999 and later.

Details of the calculation of the SJR indicator are available at http://www.scimagojr.com/SCImagoJournalRank.pdf and http://arxiv.org/ftp/arxiv/papers/0912/0912.4141.pdf.

SJR compared to Impact Factor

  • differences in the databases used as the sources of citations:
    • SJR is calculated using citation data from Scopus
    • IF is calculated using citation data from Web of Science
  • differences in the methodology of calculation of indices:
    • SJR attributes different weight to citations based on the prestige of the citing journal
    • excessive self citations are not included in calculation of SJR, because the number of references that a journal may direct to itself is limited to a maximum 33 % of its total references, which prevents the inflation of the SJR value by excess self citations leaving the normal process of self citation untouched
    • SJR normalizes for differences in citation behavior between subject fields
    • SJR is based on three-year's citation data
    • the denominator (number of articles published) of SJR includes all types of articles, not citable articles only