Table 9.

ANOVA for response surface quadratic model

Source	Degrees of freedom	Sum of square	Adjusted sum of square	Mean of square	F value	p value
Regression	9	40,429.4	40,429.4	4,492.2	30.10	0.001
Linear	3	23,800.7	15,210.1	5,070.0	33.97	0.001
Square	3	9,989.6	9,989.6	3,329.9	22.31	0.003
Interaction	3	6,639.1	6,639.1	2,213.0	14.83	0.006
Residual error	5	746.2	746.2	149.2
Lack-of-fit	3	746.2	746.2	248.7
Pure error	2	0.0	0.0	0.0
Total	14	41,175.6

R² = 98.87 %, R² (pred) = 81.91 %, R²(adj) = 96.83 %

F Fishers’s function, p corresponding level of significance