Experienced Segregation

• http://web.stanford.edu/~gentzkow/research/experienced-segregation.pdf
• Susan Athey, Billy Ferguson, Matthew Gentzkow, Tobias Schmidt

Abstract:

We introduce a novel measure of segregation, experienced isolation, that captures individuals’ exposure to diverse others in the places they visit over the course of their days. Using Global Positioning System (GPS) data collected from smartphones, we measure experienced isolation by race. We find that the isolation individuals experience is substantially lower than standard residential isolation measures would suggest, but that experienced and residential isolation are highly correlated across cities. Experienced isolation is lower relative to residential isolation in denser, wealthier, more educated cities with high levels of public transit use, and is also negatively correlated with income mobility.

Experienced isolation is measured with smartphone GPS data, with resolution of 500 feet square (“geohash7s”).

Race is not directly observed, but inferred from home location and the race composition of that location.

Main results 1. People are less segregated than resident-based isolation measures. 2. Yet they are correlated. 3. The variation is systematic. Experienced isolation is lower in higher population density, more public transit, … 4. It is negatively correlated with Chetty’s income mobility measure.