Table 2 Descriptive statistics for PM 2.5 exposure, Massachusetts, 2000–2002
Covariate | Mean | Median | SD | Range | IQR | Q1 | Q3 | Days of data available |
|---|---|---|---|---|---|---|---|---|
PM 2.5 exposure (μg/m 3 ) | 9.6 | 8.4 | 5.1 | 159.7 | 5.3 | 6.3 | 11.6 | 3285 |
Cumulative traffic density (density*length) | 1309 | 702 | 2076 | 36188 | 1352 | 258 | 1611 | 3285 |