February 22, 2011

Your City's a Sucker, My City's a Creep

I'll let the abstract speak for me on this one:

CRS, "Scaling and Hierarchy in Urban Economies", submitted to the Proceedings of the National Academy of Sciences (USA), arxiv:1102.4101
Abstract: In several recent publications, Bettencourt, West and collaborators claim that properties of cities such as gross economic production, personal income, numbers of patents filed, number of crimes committed, etc., show super-linear power-scaling with total population, while measures of resource use show sub-linear power-law scaling. Re-analysis of the gross economic production and personal income for cities in the United States, however, shows that the data cannot distinguish between power laws and other functional forms, including logarithmic growth, and that size predicts relatively little of the variation between cities. The striking appearance of scaling in previous work is largely artifact of using extensive quantities (city-wide totals) rather than intensive ones (per-capita rates). The remaining dependence of productivity on city size is explained by concentration of specialist service industries, with high value-added per worker, in larger cities, in accordance with the long-standing economic notion of the "hierarchy of central places".

Figures and calculations were done with this code and data. I realize that's not fully up to spec for reproducible computational science, but I'm getting there.

(Yes, this the paper which I started because readers kept asking me questions, and yes, A Fermi Problem in Western Pennsylvania was spun off from the first draft, which was going to be just a blog post. It turns out that the journal is OK with putting submitted manuscripts on arxiv, or at least not too upset.)

Manual trackback: Metadatta; Chris Waggoner

Self-Centered; Enigmas of Chance; The Dismal Science

Posted at February 22, 2011 00:05 | permanent link

Three-Toed Sloth