Table 2.
ANOVA for response surface quadratic model: analysis of variance table (partial sum of squares). A: temperature (°C), B: extraction time (min), and C: water-to-material ratio.
| Source | Sum of squares | DF | Mean square | F value | P value | Significant |
|---|---|---|---|---|---|---|
| Model | 50.10 | 9 | 5.566395 | 8.944987 | 0.0043 | ∗ |
| A | 5.45 | 1 | 5.445 | 8.74991 | 0.0212 | ∗ |
| B | 3.50 | 1 | 3.498013 | 5.621174 | 0.0495 | ∗ |
| C | 9.53 | 1 | 9.526613 | 15.30891 | 0.0058 | ∗∗ |
| A 2 | 0.01 | 1 | 0.01 | 0.01607 | 0.9027 | |
| B 2 | 0.1296 | 1 | 0.1296 | 0.208262 | 0.6620 | |
| C 2 | 1.199025 | 1 | 1.199025 | 1.926788 | 0.2077 | |
| AB | 8.451287 | 1 | 8.451287 | 13.5809 | 0.0078 | ∗∗ |
| AC | 8.421487 | 1 | 8.421487 | 13.53301 | 0.0079 | ∗∗ |
| BC | 10.23689 | 1 | 10.23689 | 16.45029 | 0.0048 | ∗∗ |
| Residual | 4.356045 | 7 | 0.622292 | |||
| Lack-of-fit | 1.578925 | 3 | 0.526308 | 0.758064 | 0.5731 | |
| Pure error | 2.77712 | 4 | 0.69428 | |||
| Cor. total | 54.4536 | 16 |
∗ P < 0.05 and ∗∗P < 0.01.