Generative Models of Hierarchical Systems of Cities

Cities around the world and throughout history vary greatly in terms of size; shape; and economic, social and political functioning. However, some quantifiable regularities can be observed. This chapter is devoted to presenting the explanatory processes of the hierarchization of systems of cities put forward by different scientific disciplines (geography, economics, sociology, anthropology and physics). It describes which explanatory processes are integrated and in what form into a particular family of generative models of hierarchical systems of cities, characterized by scaling laws. The chapter also distinguishes three categories of models: the first is intraurban microeconomic models; the second is statistical physics models, which postulate that intraurban social interactions are the source of urban hierarchies; and the third category includes models derived from microeconomics or statistical physics in which interurban interactions between individuals or firms are the cause of urban hierarchies.