This paper evaluates the European Paradox according to which Europe plays a leading world role in terms of scientific excellence, measured in terms of the number of publications, but lacks the entrepreneurial capacity of the U.S. to transform this excellent performance into innovation, growth, and jobs. Citation distributions for the U.S., the European Union (EU), and the rest of the world are evaluated using a pair of high- and low-impact indicators, as well as the mean citation rate. The dataset consists of 3.6 million articles published in 1998-2002 with a common five-year citation window. The analysis is carried at a low aggregation level: the 219 sub-fields identified with the Web of Science categories distinguished by Thomson Scientific. The problems posed by international co-authorship and the multiple assignments of articles to sub-fields are solved following a multiplicative strategy. In the first place, we find that, although the EU has more publications than the U.S. in 113 out of 219 sub-fields, the U.S. is ahead of the EU in 189 and 163 sub-fields in terms of the high- and low-impact indicators. In the second place, we verify that using the high-impact indicator the U.S./EU gap is usually greater than when using the mean citation rate. The authors acknowledge financial support from the Santander Universities Global Division of Banco Santander. Ruiz-Castillo also acknowledges financial help from the Spanish MEC through grant SEJ2007-67436. This paper is part of the SCIFI-GLOW Collaborative Project supported by the European Commission.s Seventh Research Framework Programme, Contract number SSH7- CT-2008-217436.
