The paper extends the methodological toolbox of measures of industrial concentration and regional specialization. First, a taxonomy is proposed which gives rise to a modular construction system for disproportionality measures based on three characteristic features: the projection function, the...

This paper attempts to model directly the "folk theorem" of spatial economics, according to which increasing returns to scale are essential for understanding the geographical distributions of activity. The model uses the simple structure of most New Economic Geography papers, with two identical...