Optimization of Ultrasound-Assisted Extraction of Total Flavonoids from Dendranthema indicum var. aromaticum by Response Surface Methodology

Table 4

Model summary statistics.

Source	Standard deviation	R^2	Adjusted R^2	Predicted R^2	PRESS
Linear	2.58E − 02	0.8213	0.7877	0.7295	0.0161
2FI	2.80E − 02	0.8283	0.7490	0.6024	0.0236
Quadratic	1.05E − 02	0.9814	0.9647	0.9023	0.0058	Suggested
Cubic	8.46E − 03	0.9928	0.9772	0.9595	0.0024	Biased