Table 2. PLS2 Model Calibration and Validation Metrics for D-Optimal and Seven-Level FF Designsa.
| PLS2 metrics | D-optimal | seven-level FF |
|---|---|---|
| LVs | 4 | 4 |
| Calibration Statistics | ||
| RMSEC (HNO3) | 0.092 | 0.086 |
| RMSECV (HNO3) | 0.19 | 0.090 |
| RMSEC (temp.) | 1.7 | 1.05 |
| RMSECV (temp.) | 4 | 1.36 |
| Validation Statistics | ||
| RMSEP (HNO3) | 0.078 | 0.085 |
| RMSEP % (HNO3) | 1.8 | 1.9 |
| SEP (HNO3) | 0.079 | 0.068 |
| bias (HNO3) | –0.011 | –0.053 |
| RMSEP (temp.) | 1.38 | 1.46 |
| RMSEP % (temp.) | 6.9 | 7.3 |
| SEP (temp.) | 1.32 | 1.42 |
| bias (temp.) | –0.48 | 0.45 |
a
Aside from RMSEP %, HNO3 values are in mol/L and Temp. in °C.