Mapping excellence in the geography of science: An approach based on   Scopus data
  As research becomes an ever more globalized activity, there is growing interest in national and international comparisons of standards and quality in different countries and regions. A sign for this trend is the increasing interest in rankings of universities according to their research performance, both inside but also outside the scientific environment. New methods presented in this paper, enable us to map centers of excellence around the world using programs that are freely available. Based on Scopus data, field-specific excellence can be identified and agglomerated in regions and cities where recently highly-cited papers were published. Differences in performance rates can be visualized on the map using colors and sizes of the marks. 
Lutz Bornmann, Loet Leydesdorff, Christiane Walch-Solimena, Christoph   Ettl
cs.DL