Table 2.
Regression Results of the Increase in Average PM2.5 (µg/m3) in Alternative Models
| Train type | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|
| Empty Coal | 2.27* | 5.64*** | 0.96 | 1.10 | 5.84*** | 2.19 | 6.41*** |
| Freight | 4.50*** | 7.49*** | 2.78*** | 3.05*** | 7.80*** | 5.07*** | 6.53*** |
| Full Coal | 6.79*** | 9.71*** | 5.09*** | 5.20*** | 10.00*** | 12.12*** | 8.32*** |
| R2 | 0.16 | 0.16 | 0.16 | 0.18 | 0.16 | 0.20 | 0.53 |
| n | 2829 | 2829 | 2829 | 2829 | 2829 | 1330 | 2829 |
*** p < 0.01, ** p < 0.05, * p < 0.1
Models are: (1) Basic (2) Basic + temperature (3) Basic + humidity 4) Basic + humidity + negatives = 0 (5) Basic + dew point (6) wind speed < mean (7) Calibrated monitor. (Note: Basic model includes wind speed, train speed and a binary variable for each train type, no constant)