Table 4.

Prediction performances with Norris derivate filter between valid acidity and second derivate spectra using each segment length (gap size=10 points)

Model	Segment length	No. of factors	r2	RMSEC	RMSEP
1	3	6	0.837	0.0553	0.0694
2	5	7	0.831	0.0562	0.0677
3	7	4	0.781	0.0640	0.0703
4	9	4	0.783	0.0638	0.0698
5	11	4	0.784	0.0636	0.0691
6	13	4	0.787	0.0633	0.0689
7	15	4	0.790	0.0628	0.0689
8	17	3	0.786	0.0634	0.0666
9	19	3	0.788	0.0631	0.0689
10	21	4	0.797	0.0617	0.0665

r ²: Correlation coefficient of determination