Table 2.

RMSE of PCR analysis on preprocessed spectra.

	Exponential	Polynomial	Sigmoid	Sine
airPLS	0.0216	0.0202	0.0206	0.0208
MPLS	0.0226	0.0214	0.0224	0.0208
MSBC	0.0249	0.0248	0.0248	0.0249
AS airPLS	0.0181	0.0185	0.0185	0.0185
CW airPLS	0.0219	0.0188	0.0189	0.0189
AS MPLS	0.0186	0.0180	0.0190	0.0188
CW MPLS	0.0203	0.0196	0.0199	0.0193