Fig. 4: Association between upward income mobility and EC across counties.

Scatter plot of upward income mobility against economic connectedness (EC) for the 200 most populous US counties. EC is defined as twice the share of above-median-SES friends among below-median-SES individuals living in the county. Upward income mobility is obtained from the Opportunity Atlas⁷² and is measured as the predicted household income rank in adulthood for children in the 1978–1983 birth cohorts with parents at the 25th percentile of the national income distribution. We report a slope estimated using an ordinary least squares (OLS) regression on the 200 largest US counties by population, with standard errors clustered by commuting zone in parentheses. We also report the population-weighted correlation between upward mobility and EC across both the 200 largest counties as well as all counties, with standard errors (clustered by commuting zone) in parentheses. The correlations and regression are weighted by the number of children in each county whose parents have below-national-median income.