Frenken, Koen; Oort, Frank G. van; Verburg, Thijs; … - Disciplinegroep Economische Geografie, Faculteit … - 2004
In economic theory, one can distinguish between variety as a source of regional knowledge spillovers, called Jacobs externalities, and variety as a portfolio protecting a region from external shocks. We argue that Jacobs externalities are best measured by related variety (within sectors), while...