Fig. 3: Results of the full boosted classification tree analysis.
The left panel displays the relative variable importance of environmental and demographic indicators strongly associated with a redlined neighborhood compared to a non-redlined neighborhood. Predictors that exceed the dashed line (i.e., randomness threshold of 100/14, or 7.14%) are considered important factors that are most indicative of an area having been redlined. Gray bars are environmental indicators; white bars are demographic indicators. The right panel displays the partial dependency plots for the four environmental indicators above the randomness threshold in order of decreasing relative importance (from left to right, top to bottom): proximity to risk management plan sites (count); hazardous noise indicator (% road noise exposure >70 dBA); diesel particulate matter (PM, µg/m3); and air cancer toxics risk (risk in 1 million). The black line signifies the smoothed partial dependency plot.
