Primary predictors of TNCO yields
| Parameter | B | SE | Hypothesis test | |||
|---|---|---|---|---|---|---|
| Dependent variable | Wald χ2 | df | Significance | |||
| Tar* | Year | −0.046 | 0.0113 | 16.986 | 1 | <0.001 |
| Ventilation | −0.010 | 0.0015 | 46.037 | 1 | <0.001 | |
| Per cigarette tobacco weight | 0.625 | 0.2694 | 5.383 | 1 | 0.020 | |
| Nicotine | Year | −0.029 | 0.0090 | 10.704 | 1 | 0.001 |
| Ventilation | −0.008 | 0.0012 | 42.441 | 1 | <0.001 | |
| Per cigarette tobacco weight | 0.399 | 0.1572 | 6.459 | 1 | 0.011 | |
| CO* | Year | −0.029 | 0.0099 | 8.649 | 1 | 0.003 |
| Ventilation | −0.009 | 0.0011 | 66.476 | 1 | <0.001 | |
| Per cigarette tobacco weight | 0.529 | 0.1900 | 7.742 | 1 | 0.005 | |
| Filter density | −0.001 | 0.0003 | 5.690 | 1 | 0.017 | |
*GEE with gamma distribution and log link function.
GEE, generalised estimating equations.
TNCO, tar, nicotine and carbon monoxide.