Ergodic Properties of Urban Street Networks in the UK

In this paper we study the statistical properties of urban street networks. We show that urban and non-urban street networks can be differentiated through their statistical properties, suggesting at a transition between two phases. We introduce a definition of city boundaries based on the percolation properties of the network in the street intersection density space, through the concept of city condensation threshold. Finally, using an historical dataset covering the growth of London during 224 years, we show that some global statistical measures display the same time and space evolution, i.e. they seem to be ergodic properties.