Journal maps on the basis of Scopus data: A comparison with the Journal Citation Reports of the ISI

Abstract Using the Scopus dataset (1996–2007) a grand matrix of aggregated journal‐journal citations was constructed. This matrix can be compared in terms of the network structures with the matrix contained in the Journal Citation Reports ( JCR ) of the Institute of Scientific Information (ISI). Because the Scopus database contains a larger number of journals and covers the humanities, one would expect richer maps. However, the matrix is in this case sparser than in the case of the ISI data. This is because of (a) the larger number of journals covered by Scopus and (b) the historical record of citations older than 10 years contained in the ISI database. When the data is highly structured, as in the case of large journals, the maps are comparable, although one may have to vary a threshold (because of the differences in densities). In the case of interdisciplinary journals and journals in the social sciences and humanities, the new database does not add a lot to what is possible with the ISI databases.