TABLE 3.
ANOVA for the response surface model.
| Source | Sum of squares | Df | Mean squares | F value | p-value |
| Prop > F | |||||
| Model | 219.00 | 14 | 15.64 | 44.73 | <0.0001 |
| A- ratio of liquid to solid | 1.64 | 1 | 1.64 | 4.68 | 0.0484 |
| B-ultrasonic power | 10.35 | 1 | 10.35 | 29.60 | <0.0001 |
| C-ethanol concentration | 4.69 | 1 | 4.69 | 13.40 | 0.0026 |
| D-extraction time | 0.49 | 1 | 0.49 | 1.40 | 0.2559 |
| AB | 4.87 | 1 | 4.87 | 13.93 | 0.0022 |
| AC | 12.82 | 1 | 12.82 | 36.67 | <0.0001 |
| AD | 1.84 | 1 | 1.84 | 5.27 | 0.0376 |
| BC | 0.75 | 1 | 0.75 | 2.14 | 0.166 |
| BD | 0.00 | 1 | 0.00 | 0.00 | 0.9583 |
| CD | 0.70 | 1 | 0.70 | 1.99 | 0.1801 |
| A2 | 60.18 | 1 | 60.18 | 172.06 | <0.0001 |
| B2 | 102.81 | 1 | 102.81 | 293.97 | <0.0001 |
| C2 | 59.28 | 1 | 59.28 | 169.49 | <0.0001 |
| D2 | 0.27 | 1 | 0.27 | 0.77 | 0.3951 |
| Residual | 4.90 | 14 | 0.35 | ||
| Lack of fit | 3.35 | 10 | 0.34 | 0.87 | 0.6130 |
| Pure error | 1.55 | 4 | 0.39 | ||
| Cor total | 223.90 | 28 | |||
| R 2 | 0.98 | ||||
| Adj-R2 | 0.96 |