Quantifying Urban Centrality: A Simple Index Proposal and International Comparison

This study introduces a new measure of urban centrality. It identifies distinct urban tructures from different spatial patterns of jobs and resident population. The roposed urban centrality index constitutes an extension of the spatial separation index MIDELFART-KNARVIK et al., 2000). It is suggested that urban structure should e more accurately analyzed by considering a centrality scale (varying from extreme onocentricity to extreme polycentricity) rather than a binary variable (monocentric r polycentric). The proposed index controls for differences in size and shape of the eographic areas for which data is available, and can be calculated using different ariables, such as employment and population densities and trip generation rates. The roperties of the index are illustrated in simulated artificial data sets. Simulation results or hypothesized urban forms are compared to other similar measures proposed by revious literature. The index is then applied to the urban structure of four different etropolitan areas: Pittsburgh and Los Angeles in the United States; São Paulo, Brazil;and Paris, France, The index is compared to other traditional spatial agglomeration easures, such as global and local Moran’s I, and density gradient estimations.