Table 3.

Analysis of variance for response quadratic model Encapsulation efficiency (%).

Source	Sum of Squares	dfα	Mean square	F-value	Prob > F
Model	56.17	9	6.24	16.95	0.0006**
X1	35.74	1	35.74	97.07	<0.0001**
X2	1.54	1	1.54	4.18	0.0801
X3	1.66	1	1.66	4.50	0.0716
X1 X2	3.42	1	3.42	9.29	0.0186*
X1 X3	0.081	1	0.081	0.22	0.6529
X2 X3	0.055	1	0.055	0.15	0.7101
${\text{X}}_1^2$	4.75	1	4.75	12.91	0.0088**
${\text{X}}_2^2$	7.70	1	7.70	20.92	0.0026**
${\text{X}}_3^2$	0.21	1	0.21	0.58	0.4716
Residual	2.58	7	0.37
Lack of fit	1.81	3	0.60	3.15	0.1484
Pure error	0.77	4	0.19
Cor total	58.75	16

^αDegree of freedom.

^*Significant at 0.05 level.

^**Significant at 0.01 level.