Multivariate Calibration and Model Integrity for Wood Chemistry Using Fourier Transform Infrared Spectroscopy

Table 2

Calibration and predictive results of FT-IR based multivariate models.

Algorithm	Chemical components	Wavenumber ranges	Raw spectra			First derivative
				RMSEP	RPD		RMSEP	RPD
PLS	Extractives	1750–1250 cm^−1	73.51	1.19	1.19	86.66	0.34	4.18
	Lignin	1800–800 cm^−1	87.76	1.05	2.30	90.06	0.50	4.83
	Cellulose	1500–1000 cm^−1	56.74	1.38	1.53	85.62	0.80	1.72
	Hemicellulose	1750–800 cm^−1	79.31	2.25	1.73	92.90	1.90	2.04
PCR	Extractives	1750–1250 cm^−1	57.93	0.87	1.69	71.04	0.59	2.41
	Lignin	1800–800 cm^−1	73.70	1.51	1.60	87.36	0.82	2.94
	Cellulose	1500–1000 cm^−1	52.61	1.59	1.32	48.15	0.94	1.34
	Hemicellulose	1750–800 cm^−1	30.09	4.14	0.94	52.69	3.34	1.16