Empirical analyses of research and development find strong evidence that these activities tend to cluster geographically. Clusters are thought to emerge from the presence of localized positive externalities. This paper presents a model of this clustering behaviour. We find that phase changes in...

The objective of the paper is to develop a method through which we can identify the actors (industrial, institutional and individual) who are active in technology development in the same or similar knowledge fields. The paper is, thus, aimed to make a methodological contribution to the...