TABLE 3:
Summary of model evaluation and selection process for a case study with zinc
| Model | Scoringa | Model performanceb | Relative scoresc | Model rankd |
|---|---|---|---|---|
| Hardness | Fish = 33 | RFx,2.0 = 0.19 | Fish = 6.3 (0.26) | Fish = 3 |
| Invertebrate = 40 | 1/RFy,0.84 = 0.0078 | Invertebrate = 7.6 (0.31) | Invertebrate = 3 | |
| Algae = 0 | Algae = 0 (0) | Algae = 3 | ||
| Overall = 73 | Overall = 14 (0.57) | Overall = 4 | ||
| MLR1 | Fish = 0 | RFx,2.0 = 0.33 | Fish = 0 (0) | Fish = 4 |
| Invertebrate = 0 | 1/RFy,0.84 = 0.18 | Invertebrate = 0 (0) | Invertebrate = 4 | |
| Algae = 26 | Algae = 8.6 (4.8) | Algae = 2 | ||
| Overall = 26 | Overall = 8.6 (4.8) | Overall = 4 | ||
| MLR2 | Fish = 0 | RFx,2.0 = 0.64 | Fish = 0 (0) | Fish = 4 |
| Invertebrate = 40 | 1/RFy,0.84 = 0.41 | Invertebrate = 25.6 (16.3) | Invertebrate = 2 | |
| Algae = 0 | Algae = 0 (0) | Algae = 3 | ||
| Overall = 40 | Overall = 25.6 (16.3) | Overall = 2 | ||
| MLR3 | Fish = 22 | RFx,2.0 = 0.70 | Fish = 15.4 (6.3) | Fish = 2 |
| Invertebrate = 0 | 1/RFy,0.84 = 0.29 | Invertebrate = 0 (0) | Invertebrate = 4 | |
| Algae = 0 | Algae = 0 (0) | Algae = 3 | ||
| Overall = 22 | Overall = 15.4 (6.3) | Overall = 3 | ||
| BLM | Fish = 22 | RFx,2.0 = 0.87 | Fish = 19 (12) | Fish = 1 |
| Invertebrate = 53 | 1/RFy,0.84 = 0.53 | Invertebrate = 46 (28) | Invertebrate = 1 | |
| Algae = 26 | Algae = 23 (14) | Algae = 1 | ||
| Overall = 101 | Overall = 88 (53) | Overall = 1 | ||
a
Total of “good” scores summed for water quality and taxonomic coverage for each test, trophic level, and overall (step 4; see text).
b
RFx,2.0 = percent of predictions within a factor of 2.0; 1/RFy,0.84 = residual factor associated with 84% model accuracy (step 5; see text).
c
Product of RF and evaluation score (step 6; see text). Results presented as RFx (1/RFy).
d
Among-model ranking (step 7; see text).
BLM = biotic ligand model; MLR = multiple linear regression; RF = residual factor.