Table 2.
Characteristics of spatial variables (N = 6,301). Distribution quartiles are presented as the 25th, 50th, and 75th percentiles.
| Variable | Mean | SD | Min | Pctl. 25 | Pctl. 50 | Pctl. 75 | Max |
|---|---|---|---|---|---|---|---|
| National Walkability Index | 13.8 | 2.7 | 1 | 12.2 | 14 | 15.7 | 20 |
| Street intersection density (no autom.) | 119.86 | 120.41 | 0 | 57.24 | 107.58 | 162.1 | 5289.52 |
| Pedestrian network density | 13.12 | 9.88 | 0 | 5.77 | 11.34 | 19.44 | 121.29 |
| Traffic CO2 emissions* | 11.71 | 48.5 | 0 | 1.45 | 2.13 | 3.36 | 1964.55 |
| AADT FHWA | 11501.9 | 12641.1 | 0 | 4616.3 | 7615.9 | 12757.9 | 133216.6 |
| AADT ESRI | 13210.8 | 7107.2 | 2803.5 | 8214.5 | 11367.6 | 15918.6 | 61974.6 |
| Residential roads proximity | 0.98 | 0.04 | 0 | 0.97 | 0.98 | 1 | 1 |
| Tertiary roads proximity | 0.85 | 0.14 | 0 | 0.79 | 0.91 | 0.96 | 1 |
| Principal arterial - other proximity | 0.93 | 0.07 | 0 | 0.91 | 0.95 | 0.97 | 1 |
| Freeways Expressways proximity | 0.83 | 0.13 | 0 | 0.77 | 0.86 | 0.92 | 1 |
| Interstate highway proximity | 0.77 | 0.19 | 0 | 0.68 | 0.82 | 0.91 | 1 |
| Trunk roads proximity | 0.86 | 0.12 | 0 | 0.83 | 0.89 | 0.94 | 1 |
| Secondary roads proximity | 0.95 | 0.07 | 0 | 0.95 | 0.97 | 0.99 | 1 |
| Primary roads proximity | 0.87 | 0.14 | 0 | 0.82 | 0.91 | 0.96 | 1 |
| Motorways proximity | 0.84 | 0.14 | 0 | 0.79 | 0.88 | 0.94 | 1 |
| Barrier factor FHWA-BTS | 52.0 | 26.3 | 0 | 34.3 | 53.3 | 72.2 | 100 |
| Barrier factor OSM | 58.5 | 28.7 | 0 | 38.7 | 61.5 | 82.9 | 100 |
| Automobile intersection density | 6.34 | 29.11 | 0 | 0 | 0 | 0 | 742.21 |
| Automobile network density | 1.78 | 5.68 | 0 | 0 | 0 | 0 | 107.99 |
*
The variable Traffic CO2 emissions has 1.1% of missing data.
SD is standard deviation. Annual Average Daily Traffic (AADT). Federal Highway Administration (FHWA). Environmental Systems Research Institute (ESRI). OpenStreetMap (OSM).
Bureau of Transportation Statistics (BTS, US Department of Transportation).