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Research Metrics

Impact Factor

"Impact Factor" is a trademarked name for the measure of impact a journal has relative to citations received according to Web of Science. 

The most common tools for calculating the impact factor are...

  • Scopus - SNIP
  • Scopus - SJR


Source Normalised Index per Paper (SNIP) 

Sourced from Scopus, this measures a journals contextual citation impact by weighting citations based on the total number of citations in a subject field.  It helps to make direct comparisons between journals in different subject fields. 

SNIP is the ration of a journals average citation count per paper and the citation potential of its subject field. 

The citation potential of a source's subject field is the average number of references per document citing that source. It represents the likelihood of being cited for documents in a particular field. A source in a field with a high citation potential tends to have a high impact per paper.

Citation potential is important because it accounts for the fact that typical citation counts vary widely between research disciplines. For example, they tend to be higher in life sciences than in mathematics or social sciences. If papers in one subject field contain an average of 40 cited references while those in another contain an average of 10, then the former field has a citation potential that is 4 times higher than that of the latter.

Ideally you want a SNIP over 1.



SCImago Journal Ranking (SJR)

Sourced from Scopus, this is a weighted by the prestige of the journal, so a citation from a journal with a high SJR is worth more. Subject field, quality, and reputation of the journal have a direct effect on the value of a citation.

Ideally you want an SJR over 1.  


SJR metrics and other journal metrics can also be found on the SCImago Journal Rankings website.

  1. Connect to SJR
  2. Click on Journal Search
  3. Enter the search terms and click Search
  4. Select the journal you wish to view

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