SJR and SNIP journal metrics
The Scopus database offers two journal metrics:
- SCImago Journal Rank (SJR)
- Source Normalized Impact per Paper (SNIP)
SJR starts with the concept that citations aren’t equal, and accordingly gives greater weight to citations from high SJR journals. SNIP combines a journal’s average citation count per paper with the "citation potential" of its subject area, thereby enabling journals in different subject areas to be compared. For further information about these two journal metrics: SJR and SNIP
SRJs can be analysed by subject area, subject category and country using the SCImago Journal and Country Rank portal. This portal can also be used to compare three or four individual journals – the results are presented in a table and graphically. The SRJ portal is powered by Scopus and based on Scopus data. Data is available from 1999 onwards.
HEFCE has announced that the Scopus database will be used for bibliometric data to support the 2014 REF, which suggests using SJR to identify appropriate journals in which to publish. However, there hasn’t been any official REF advice on this.
To find a journal’s SJR and SNIP:
- Open Scopus
- Link to <Analytics> on the blue bar
- Click in the <search box>, beneath Journal Analyser
- Enter a journal title in the box
- Link to the <Search> button
- Double click on the journal’s title in the results column
- See chart appear
- Move between tabs to view SJR and SNIP charts
- Repeat for other journals
How do the journal metrics provided by Scopus (SJR and SNIP) compare with those provided by Journal Citation Reports, e.g. the journal impact factor?
Scopus covers more journals than Journal Citation Reports (18,000 for Scopus versus 10,600 for JCR). This might mean that you can find your key journals in Scopus, if they aren’t available in JCR, although some journals are covered by JCR and not by Scopus. New journals tend to be picked up more quickly by Scopus than JCR, because JCR requires three years of data for calculating a journal impact factor.
JCR and the SCImago Journal and Country Rank portal both offer the facility to display data by subject areas. However, the SJR portal gives greater flexibility in presenting this data, e.g. the results can be presented in a graph.
If you are interested in cross subject journal comparisons, then Scopus’ SNIP is clearly attractive. On the other hand, the traditional journal impact factor, which is found in the JCR, has the advantage of familiarity. Its calculation is also relatively easy to understand.