Table 1.

Results of models with different spectral pre-treatments.

Regression Algorithm	Pre-Treatment	Calibration		Prediction
		R 2	RMSE	R 2	RMSE
PLS	ORIG	0.6086	0.4149	0.4636	0.4642
	SG	0.6093	0.4145	0.4674	0.4625
	SG-SNV	0.7049	0.3602	0.6753	0.3612
	GF-SNV	0.7057	0.3597	0.6720	0.3630
	MSC	0.7452	0.3348	0.5853	0.4082
LS-SVM	ORIG	0.9772	0.1339	0.6017	0.4000
	SG	0.9808	0.1239	0.5350	0.4322
	SG-SNV	0.9988	0.0321	0.8857	0.2142
	GF-SNV	0.9785	0.1301	0.8872	0.2129
	MSC	0.9966	0.0533	0.8269	0.2637