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ROAD resources covered by SNIP:"SNIP"

Name: SNIP (Source Normalized Impact per Paper)

Category of service: journal indicators

Owner:  Centre for Science and Technology Studies, Leiden University (CWTS, Netherlands). CWTS indicators are based on the Scopus bibliographic database produced by Elsevier.


Other indicators calculated by CWTS:  RIP (raw impact per publication); P (number of publications of a source in the past three years); % self cit (percentage of self citations of a source)

Coverage: international, multidisciplinary

Number of publications covered: around 20 000

Creation date: 2009 (revised in 2012)


Lists of CWTS indicators:

Reference documents: 

- Some modifications to the SNIP journal impact indicator (Ludo Waltman, Nees Jan van Eck,Thed N. van Leeuwen, Martijn S. Visser, 2013) (preprint)

- Measuring contextual citation impact of scientific journals (Henk F. Moed, 2009)


Last update: September 2015