PLS results for the prediction of chick hatching time for different pre-processing techniques based on 4-days incubated egg spectra.

Table 1: PLS results for the prediction of chick hatching time for different pre-processing techniques based on 4-days incubated egg spectra.

Pre-processing method	PCs	r_cal	RMSEC (hours)	r_pred	RMSEP (hours)	Bias
Normalized spectra	7	0.876	2.76	0.882	3.62	-0.861
SG smoothing^a	7	0.872	2.8	0.88	3.65	-0.863
MSC	4	0.852	3.04	0.856	3.49	-0.769
Baseline offset correction	7	0.878	2.79	0.885	3.6	-0.825
SG first derivativea	5	0.864	2.94	0.848	3.72	-0.932

r_cal and r_pred are the correlation coefficient for calibration and prediction set, respectively; SG: Savitzky-Golay method; ^aNumber of segments: 5, Polynomial order: 2.