Aggregated journal-journal citation relations in Scopus and Web-of-Science
matched and compared in terms of networks, maps, and interactive overlays

We compare the network of aggregated journal-journal citation relations
provided by the Journal Citation Reports (JCR) 2012 of the Science and
Social Science Citation Indexes (SCI and SSCI) with similar data based on
Scopus 2012. First, global maps were developed for the two sets separately;
sets of documents can then be compared using overlays to both maps. Using
fuzzy-string matching and ISSN numbers, we were able to match 10,524 journal
names between the two sets; that is, 96.3% of the 10,930 journals contained
in JCR or 51.2% of the 20,553 journals covered by Scopus. Network analysis
was then pursued on the set of journals shared between the two databases and
the two sets of unique journals. Citations among the shared journals are
more comprehensively covered in JCR than Scopus, so the network in JCR is
denser and more connected than in Scopus. The ranking of shared journals in
terms of indegree (that is, numbers of citing journals) or total citations
is similar in both databases overall (Spearman's rho > 0.97), but some
individual journals rank very differently. Journals that are unique to
Scopus seem to be less important--they are citing shared journals rather
than being cited by them--but the humanities are covered better in Scopus
than in JCR. 


Loet Leydesdorff, Félix de Moya-Anegón, and Wouter de Nooy 


** preprint available at 

** apologies for cross-postings



Loet Leydesdorff 

University of Amsterdam
Amsterdam School of Communications Research (ASCoR)

 <mailto:[log in to unmask]> [log in to unmask]