Tipping and the Dynamics of Segregation
利用1970-2000年美国人口普查数据，通过断点回归方法检验谢林模型中的“小费点”是否存在，发现白人人口流动在少数族裔占比5%-20%时出现类似小费行为的非线性变化，且小费点与白人种族态度相关。
Schelling ("Dynamic Models of Segregation, " Journal of Mathematical Sociology 1 (1971), 143–186) showed that extreme segregation can arise from social interactions in white 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 1970 through 2000 to test for discontinuities in the dynamics of neighborhood racial composition. We find strong evidence that white population flows exhibit tipping-like behavior in most cities, with a distribution of tipping points ranging from 5% to 20% minority share. Tipping is prevalent both in the suburbs and near existing minority enclaves. In contrast to white population flows, there is little evidence of nonlinearities in rents or housing prices around the tipping point. Tipping points are higher in cities where whites have more tolerant racial attitudes.