Robert J. W. Tijssen

TL;DR: In this article, the authors analyzed the changing effect of physical distance and territorial borders on the intensity of research collaboration across European regions and found that the bias to collaborate with physically proximate partners did not decrease, while the bias towards collaboration within territorial borders did decrease over time.

TL;DR: The authors conclude that the value of impact indicators of research activities at the level of an institution or a country strongly depend upon whether one includes research publications in SCI covered journals written in other languages than in English.

TL;DR: The Leiden Ranking 2011/2012 as discussed by the authors is a ranking of universities based on bibliometric indicators of publication output, citation impact, and scientific collaboration, which includes 500 major universities from 41 different countries.

TL;DR: The Leiden Ranking is compared with other global university rankings, in particular the Academic Ranking of World Universities (commonly known as the Shanghai Ranking) and the Times Higher Education World University Rankings, and the comparison focuses on the methodological choices underlying the different rankings.

TL;DR: The paper concludes that, in an analysis of collaborative links, it is essential to use both absolute and relative measures, which normalize differences in country size.