TABLE 2.
Parameter estimates from two logistic regression models used to explain Cluster F and G frequencies in relation to selected geochemical measurements
| Parametera | Cluster F
|
Cluster G
|
||
|---|---|---|---|---|
| Estimate | P > Chi square | Estimate | P > Chi square | |
| Full model | ||||
| Intercept | −3.6181 | 0.009 | −0.6515 | 0.554 |
| Sulfate | 0.000969 | 0.038 | −0.00029 | 0.453 |
| DO | 0.8999 | 0.015 | −0.1827 | 0.647 |
| Uranium | −0.00416 | 0.047 | 0.00183 | 0.258 |
| Nitrate | −0.00066 | 0.088 | 0.000532 | 0.049 |
| Model with U(VI) as sole variable | ||||
| Intercept | −0.5934 | 0.1421 | −1.4794 | 0.0008 |
| Uranium | −0.00055 | 0.1086 | 0.00111 | 0.0005 |
a
P values of the full model are 0.0074 for cluster F and 0.0007 for cluster G. The P values of the model with U(VI) as the sole variable are 0.0902 for cluster F and 0.0001 for cluster G.