What is an urban structure? : Challenge of foreseeing 21st century spatial patterns of the urban economy

For example, urban structure can refer to the sociological structures of urban communities (Axelrod, 1956), to the spatial configuration of land uses at the metropolitan scale (Harris & Ullman, 1945), to the relative location of residences and workplaces (Giuliano, 1993), to the spatial distribution of economic activity in cities (Anas et al, 1998), to the geography of population densities (Wang a [...] However, in the context of the study of urban areas, it is important to clarify the distinction between urban patterns (which are instantaneous photographs of the configuration of urban actors) and urban spatial structures (which are patterns that are either constant through time or that evolve under the influence of particular processes). [...] It is difficult to refute the idea that a city has multiple structures: even in the very focussed area concerned with processes that govern the intra-metropolitan location of high-order services, the processes that govern the location of new-build office space (Lang, 2003) are not necessarily the same as those that govern the location of management consultant employment (Shearmur & Alvergne, 2002) [...] Both the table and the figure highlight the fact that the processes are not straightforward: Table 1 provides an outline of the way in which each process influences itself (by way of feedback), and influences the other processes (as the outcomes of one process become factors to be taken into account in the two other processes). [...] In terms of the processes described in Table 1 and Figure 1, the central location of power can be interpreted – from an economic viewpoint – as the spatial result of agents‟ willingness to pay for good accessibility to the institutions of power.