Table 8 Evolution of the standard deviation of residuals for various GRNN models predicting F a and F v in the RP–RF case
Number of parameters | Explanatory parameters | F a | F v | ||
|---|---|---|---|---|---|
Standard deviation of residuals | Variance reduction | Standard deviation of residuals | Variance reduction | ||
All (6) | Depth + f 0 + V sm + C v + V s30 + V bedrock | 0.0020 | 99.9% | 0.00023 | 99.9% |
3 (best triplet) | f 0 + C v + V s30 | 0.0094 | 99.6% | 0.0067 | 99.5% |
2 (best pair) | f 0 + C v | 0.0349 | 94.9% | 0.0173 | 97.0% |
2 (convenient pair) | f 0 + V s30 | 0.1083 | 50.7% | 0.0515 | 73.2% |
1 (best for Fa) | C v | 0.0878 | 67.6% | 0.0786 | 37.6% |
1 (best for Fv) | f 0 | 0.1355 | 22.9% | 0.0661 | 55.9% |
1 (usual) | V s30 | 0.1419 | 15.4% | 0.0752 | 42.9% |
Initial σ | 0.1543 | 0.0995 | |||