Table 1.

Performance of univariate regression and PLSR (partial least squares regression) models.

		Univariate			PLSR
		Model 1	Model 2	Model 3
	Input variables	B	E	G	A–H
Accuracy	RMSEP	6.39%	5.88%	5.92%	5.46%
	RMSEC	4.66%	4.66%	6.55%	4.45%
Calibration	Slope	−1.027	−0.515	1.021	0.988
	Intercept	0.978	0.949	0.829	0.005
	R2	0.987	0.987	0.974	0.988
Validation	Slope	1.004	0.990	1.027	1.024
	Intercept	−0.031	−0.030	−0.056	−0.035
	R2	0.967	0.976	0.984	0.977