Source

Sum of squares

DF

Mean square

P-value

F-value

Model
Residual (error)
Lack of Fit
Pure Error
Correlation Total

191.61
0.64
0.21
0.076
191.81

9
7
3
4
17

21.29
0.091
0.071
0.019

515.92

3.72

<0.0001

0.1186

R2= 0.9985 Adj R2 = 0.9966    Predicted R2= 0.9817 Adeq. Precision = 63.404

Table 4: Analysis of variance (ANOVA) for the quadratic response surface model fitting to the biodegradation data of kerosene oil.