Extended Data Fig. 3: Friending Bias versus Racial Diversity.

This figure presents binned scatter plots of friending bias against racial diversity within colleges (green diamonds) and neighbourhoods (ZIP codes, orange circles). See notes to Extended Data Fig. 1 for details on construction of binned scatter plots. We define racial diversity as \((1-{\Sigma }_{i}{s}_{i}^{2})\), where s_i is the fraction of race/ethnicity i (Black, white, Asian, Hispanic, Native American). Friending bias is defined as the average among below-median-SES individuals in the group (i.e., college or neighbourhood) of one minus the ratio of the share of above-median-SES friends in each individual’s group to the share of above-median-SES peers in that group. For comparability, both series measure SES using own SES rank in adulthood and use data from the 1986–1996 birth cohorts. Racial shares for each college and ZIP code are obtained from the 2013 Integrated Post-Secondary Education Data System (IPEDS) and the 2018 American Community Survey (ACS), respectively.