Table 8.
PLSR results of combine data with second derivative and their preprocessing at a spectral sampling range of 729–975 nm.
| All Together | Pre-Processing | LV | Calibration | Prediction (Validation) | RPD | |||
|---|---|---|---|---|---|---|---|---|
| R2 | RMSEC | R2 | RMSEP | Bias | ||||
| Combine | Second derivative | 11 | 0.652 | 1.9338 | 0.651 | 1.9512 | 0.018924 | 1.7066 |
| MSC | 10 | 0.656 | 1.9233 | 0.667 | 1.9049 | −0.027812 | 1.7481 | |
| SNV | 10 | 0.657 | 1.9201 | 0.665 | 1.9107 | −0.021354 | 1.7428 | |
| OSC | 4 | 0.654 | 1.9305 | 0.651 | 1.9364 | 0.02903 | 1.7196 | |
| SNV + OSC | 7 | 0.663 | 1.9033 | 0.674 | 1.8786 | −0.015084 | 1.7725 | |
| MSC + SNV | 7 | 0.632 | 1.9884 | 0.633 | 2.0067 | −0.020487 | 1.6594 | |
| MSC + OSC | 7 | 0.662 | 1.9056 | 0.689 | 1.8286 | −0.019629 | 1.8210 | |
| Autoscale | 10 | 0.652 | 1.934 | 0.669 | 1.887 | 0.025924 | 1.7647 | |