Table 6.
Best results of each area with second derivative data and their preprocessing at a spectral sampling range of 729–975 nm using partial least square regression (PLSR).
| Area | Pre-Processing | LV | Calibration | Prediction (Validation) | RPD | |||
|---|---|---|---|---|---|---|---|---|
| R2 | RMSEC | R2 | RMSEP | Bias | ||||
| G | Second derivative | 6 | 0.71 | 1.7832 | 0.72 | 1.7136 | −0.28473 | 1.9024 |
| M | MSC + SNV | 8 | 0.759 | 2.016 | 0.750 | 2.0846 | −0.12002 | 2.0051 |
| S | SNV | 9 | 0.718 | 2.0371 | 0.723 | 1.8521 | 0.068707 | 1.9437 |
| W | MSC + OSC | 4 | 0.835 | 0.92495 | 0.747 | 1.1514 | −0.041329 | 2.0149 |
| Y | MSC + SNV | 11 | 0.662 | 1.0695 | 0.671 | 1.0343 | 0.16688 | 1.9336 |