Tipping and the Dynamics of Segregation in Neighborhoods and Schools

In a classic paper, Schelling (1971) showed that extreme segregation can arise from social interactions in preferences: once the minority share in a neighborhood exceeds a "tipping point", all the whites leave. We use regression discontinuity methods and Census tract data from the past four decades to test for the presence of discrete nonlinearities in the dynamics of neighborhood racial composition. White mobility patterns in most cities exhibit tipping-like behavior, with a range of tipping points centered around a 13% minority share. These patterns are very pronounced during the 1970s and 1980s, and diminish but do not disappear in the 1990s. We find similar dynamic patterns in neighborhoods and in schools. A variety of specification checks rule out the possibility that the discontinuity in the initial minority share is driven by income stratification or other factors, and underscore the importance of white preferences over neighbors' race and ethnicity in the dynamic process of segregation. Finally, we relate the location of the estimated tipping points in different cities to measures of the racial attitudes of whites, and find that cities with more racially tolerant whites have higher tipping points.