Seeing Urban Change: NYC Building Photos

There was a cool article in the Times yesterday about photos taken of each property in the city for tax purposes in the 1930s and again in the 1980s. The article is very relevant to yesterday's workshop, which I think got all of us thinking about how we can use mapping and pictures in our research and presentations of our work. The article links to the city's trove of pictures, which you can look up by address.

The Future of Housing in America

Last week, Housing and Urban Development Secretary Shaun Donovan spoke at Harvard’s Graduate School of Design. Invigorating an auditorium full of scholars, professionals, and members of the general public, Donovan outlined his vision for the future of housing policy in America.

He detailed three general—albeit fascinating—principles that will guide HUD in the current administration:

1) Collaboration with private and third-sector organizations (non-profit community development corporations, resident groups, etc) to bolster civic engagement and embolden federal initiatives

2) A shift to a metropolitan focus, noting the changing nature of cities and suburbs and accounting for the increase of suburban poverty and the permeability of urban borders

3) A data-driven approach to policy formation and evaluation

All general points, to be sure. But they are principles that reflect current research on urban change and illustrate a new administration that values—indeed, requires—future research on urban social processes.

Donovan also discussed a groundbreaking interagency partnership between his department, the Environmental Protection Agency, and the Department of Transportation. Proposed policies include incorporating transportation costs into mortgage values as well as a concerted effort to build new affordable housing alongside new and existing public transit options. More information on this meeting can be found at Social Science Lite, where I wrote about this exciting new partnership last June.

Measuring Gentrification

I have been puzzling over how to measure gentrification quantitatively. Drawing on the work of geographer Elvin Wyly and others who have used disciminant analysis to compare qualitative investigations of gentrified tracts with Census data, I look at 5 Census variables that have been shown to best "discriminate" between gentrified and non-gentrified tracts. These are: change in median household income, change in median rent, change in median house value, change in proportion of residents who have a BA, and change in proportion of residents working in "high-status" (managerial, professional, or technical) occupations.

I investigate how these have changed for all central-city Census tracts from 1990 to 2000. I use a relative measure of change--has the Census tract experienced an increase in each indicator that is greater than the average increase for the city in which the tract is located? A principal components analysis of changes in these 5 variables results in two "types" of gentrification indicators: (1) Changes in Capital: changes in median household income, rent, and house value; and (2) Changes in Status: changes in proportion of residents with a BA or working in high status jobs. Based on these two typologies and descriptive statistics on the changes from 1990 to 2000, I created thresholds for gentrification: (1) An increase that is 10 percentage points higher than the average change for the city in ALL three capital variables; and (2) An increase that is 5 percentage points higher than the average change for the city for BOTH status variables. From 1990 to 2000 in the United States, about 15% of all central-city tracts in the U.S. experienced gentrification based on changes in capital, about 8% experienced gentrification based on changes in status, and about 3% experienced gentrification based on both dimensions (i.e., they experienced changes above the thresholds for all 5 variables).

To see how these indicators stacked up, I mapped them for Boston. Non-shaded tracts experienced no gentrification, the lightest gray indicates gentrification based on capital, the medium gray indicates gentrification based on status, and the dark gray indicates gentrification based on both measures. I also included boundary lines for the Boston neighborhoods. Given my knowledge of Boston from 1990-2000, this map looks pretty good to me--we see the gentrification of Jamaica Pond, East Southie, the creation of the mixed income community of Harbor Point in Dorchester, and action in Allston-Brighton and Charlestown. I haven't investigated every tract--and perhaps being consistent with locally understood gentrification is less important than sticking with a defined theoretical concept (social upgrading of residents). But I think I've made some progress in measuring gentrification with Census data.

Welcome!

Cityophile (noun)

1. One who enjoys the various sights and sounds of city life
2. Researcher investigating urban phenomena
3. Person obsessed with all things related to cities

Welcome to the Cityophiles Blog! This is the online community for the Urban Social Processes Workshop atHarvard University. We envision this blog serving several purposes: (1) to provide a forum to continue conversations and debates that begin in the workshop; (2) to allow workshop members to share work in progress and get feedback from the Cityophiles community; (3) to facilitate conversation about recent publications of interest to Cityophiles; and (4) to build a community of researchers interested in all things urban.

We encourage you to comment on posts to make this a truly interactive forum. Please identify yourself in some way to make following up in person easier (if you don't want to use your full name, use initials, first name only, etc). If you are interested in posting, please email cityophiles@gmail.com for instructions.

Enjoy!

~The Cityophiles