Do People Shape Cities, or Do Cities Shape People? The Co-evolution of Physical, Social, and Economic Change in Five Major U.S. Cities
Urban change involves transformations in the physical appearance and the social composition of neighborhoods. Yet, the relationship between the physical and social components of urban change is not well understood due to the lack of comprehensive measures of neighborhood appearance. Here, we introduce a computer vision method to quantify change in physical appearance of streetscapes and generate a dataset of physical change for five large American cities. We combine this dataset with socioeconomic indicators to explore whether demographic and economic changes precede, follow, or co-occur with changes in physical appearance. We find that the strongest predictors of improvement in a neighborhood’s physical appearance are population density and share of college-educated adults. Other socioeconomic characteristics, like median income, share of vacant homes, and monthly rent, do not predict improvement in physical appearance. We also find that neighborhood appearances converge to the initial appearances of bordering areas, supporting the Burgess “invasion” theory. In addition, physical appearance is more likely to improve in neighborhoods proximal to the central business district. Finally, we find modest support for “tipping” and “filtering” theories of urban change.
We would like to acknowledge helpful comments from Gary Becker, Jörn Boehnke, Steven Durlauf, James Evans, Jay Garlapati, Lars Hansen, James Heckman, John Eric Humphries, Jackie Hwang, Priya Ramaswamy, Robert Sampson, Zak Stone, Erik Strand, and Nina Tobio. Mia Petkova contributed Figure 2. N.N. acknowledges the support from The MIT Media Lab consortia; S.D.K. acknowledges support from the National Science Foundation (grants CCF-1216095 and SES-1459912), the Harvard Milton Fund, the Wu Fund for Big Data Analysis, and the Human Capital and Economic Opportunity Working Group (HCEO) sponsored by the Institute for New Economic Thinking (INET); E.L.G. acknowledges support from the Taubman Center for State and Local Government; and C.A.H. acknowledges support from Google’s Living Lab awards and The MIT Media Lab consortia. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.
Edward L. Glaeser
I have received speaking fees from organizations that organize members that invest in real estate markets, including the National Association of Real Estate Investment Managers and the Pension Real Estate Association.