Fig. 2: Differentiated access to PCE for White and Black people in the walking scenario.

We first investigated the differentiated access between the two races to the three categories of PCE taking Harris County as an example, a Visualization of the distribution of PCE accessibility for the overrepresented CBGs of White and Black people. We used White people fraction of the CBG population to compute the average White population fraction (aWf) across all CBGs (approximately 42%). Similarly, we computed the average Black population fraction (aBf) (approximately 17%). PCE accessibility in CBGs with a White fraction of greater than aWf (left), and in CBGs with a Black population fraction of greater than aBf (right). b Probability density curves for the two races for the three categories of PCE accessibility, a kernel smoothed density curve was adopted because the data do not obey a Gaussian distribution, in order to put the probability density curves of the three PCEs together, we took the PCE accessibility as a logarithm with a base of ten. We then examined the overall potential inequities of the selected counties. c Overall PCE accessibility in overrepresented CBGs. There are 22026 overrepresented CBGs for White people and 11628 overrepresented CBGs for Black people, the height of the bar chart represents the mean PCE accessibility of the selected CBGs, the error bars show the 95% confidence interval of the statistical data, and the error bars are equivalent throughout the figure. The statistical data do not obey a normal distribution, so the Mann-Whitney U test in the nonparametric t-test was used to test whether the difference between the two groups of data was significant, * denotes the degree of significance, i.e., the P value, ***P < 0.001, **P < 0.01, *P < 0. 05, ns means P ≥ 0. 05.