Converging to the City: a Myriad Trajectories

One of the most difficult issues in urban analytics is to portray local complexity and to visualize how that complexity changes over space. We present here an approach that captures ethnic or other composition changes across all scales within a metropolitan area. Underpinning this approach is an entirely novel multi-scalar and multi-focal method to describe a city, both qualitatively and quantitatively, from a myriad of viewpoints – thus revealing the complex intertwining of local neighbourhoods into the broader pattern of the full-scale city, in all its dazzling variety.
We illustrate this approach using data from two cities: Paris and Los Angeles. Our method provides excellent visual measures of the patterns of mixing across urban space, while the graphical trajectories reveal the spatial speed at which the process of convergence takes place.