  Urban scaling, the superlinear increase of social and economic measures with
increasing population, is an ubiquitous and well-researched phenomenon. This
article is focused on socio-economic performance scaling, which could possibly
be driven by increasing returns of the spatial size and density of interaction
networks. If this is indeed the case, we should also find that spatial barriers
to interaction affect scaling and cause local performance deviations. Possible
barring effects of municipal boundaries are particularly interesting from the
perspective of urban area governance policy and regional cooperation. To our
best knowledge, this is the first study on this politically relevant and
strongly disputed subject. We test the hypothesis of possible barring effects
of municipal boundaries by correlating municipal boundaries with the structure
of commuter networks within a large densely urbanized region, the Randstad in
The Netherlands. The measured network impacts of these boundaries are
subsequently correlated with local employment deviations. In order to spatially
pinpoint correlations, we apply advanced spatially weighted modelling
technique. We find that municipal borders have significant effects on
inter-municipal commuting. Moreover we can indicate the specific effect of
individual municipal borders precisely on the map. The results show
particularly significant correlations along dividing lines between large urban
agglomerations and rural communities. The southern part of the Randstad is more
fragmented by such dividing lines than the northern part, which could partly
explain the diverging economic development between the two parts.
