Table 5.
Source/target domain | Pretreatment | Model | Calibration seta | Validation setb | Prediction setc | |||
---|---|---|---|---|---|---|---|---|
R2 | RMSE | R2 | RMSE | R2 | RMSE | |||
LMY24/XLZ53 | None | PLS | 0.719 | 4.792 | 0.663 | 5.596 | 0.696 | 5.235 |
SVR | 0.733 | 4.297 | 0.629 | 5.113 | 0.667 | 4.834 | ||
Fine-tuned CNN | 0.850 | 3.225 | 0.796 | 3.786 | 0.842 | 3.327 | ||
Fine-tuned CNN using a smaller set | 0.885 | 2.901 | 0.802 | 3.730 | 0.811 | 3.643 | ||
FD + SNV | PLS | 0.821 | 3.600 | 0.754 | 4.359 | 0.777 | 4.098 | |
SVR | 0.761 | 4.065 | 0.662 | 4.877 | 0.761 | 4.090 | ||
Fine-tuned CNN | 0.909 | 2.505 | 0.850 | 3.248 | 0.870 | 3.020 | ||
Fine-tuned CNN using a smaller set | 0.914 | 2.451 | 0.815 | 3.613 | 0.853 | 3.207 | ||
XLZ53/LMY24 | None | PLS | 0.538 | 5.749 | 0.586 | 5.423 | 0.559 | 5.810 |
SVR | 0.537 | 5.537 | 0.561 | 5.429 | 0.506 | 5.759 | ||
Fine-tuned CNN | 0.850 | 3.156 | 0.746 | 4.129 | 0.757 | 4.036 | ||
Fine-tuned CNN using a smaller set | 0.734 | 4.235 | 0.672 | 4.691 | 0.689 | 4.568 | ||
FD + SNV | PLS | 0.637 | 5.140 | 0.630 | 5.086 | 0.636 | 5.300 | |
SVR | 0.654 | 4.909 | 0.664 | 4.928 | 0.578 | 5.445 | ||
Fine-tuned CNN | 0.889 | 2.708 | 0.835 | 3.332 | 0.822 | 3.460 | ||
Fine-tuned CNN using a smaller set | 0.892 | 2.697 | 0.822 | 3.458 | 0.796 | 3.703 |
aCalibration set means the calibration set of the target domain; bValidation set means the validation set of the target domain; cprediction set means the prediction set of the target domain; the numbers are bolded to highlight models with relatively good results.