Airport noise in Atlanta : the inequality of sound

We examine how changes in the geographic concentrations of Hispanic and African-American populations are correlated with changes in probabilities of airport noise, in Atlanta, during 2003 and 2012. We estimate ordered probit and locally weighted ordered probit regressions for three different noise categories to determine the correlations between these two demographic groups and the aircraft noise levels experienced by people in individual houses that sold. Then we determine the average coefficient for all houses sold in each Census block group, and we plot each year's coefficients for each block group against the percentiles of the minority population. While the absolute level of noise has declined over the geographic area considered in 2012 compared with 2003, we find that the distribution of noise coefficients among Hispanics and blacks became more inequitable in 2012 compared with 2003. At least two potential mechanisms could generate these correlations. Due to residential mobility, income and preferences could combine to produce a concentration of minorities in certain neighborhoods. Or, perhaps noisier flight paths are imposed upon higher minority neighborhoods as a result of discrimination. Our findings contribute to the broader literature on environmental justice, even though we cannot definitively infer the mechanisms at work