Table 6 Statistical model summary of citric acid and effersoda on hardness
Source of variation | DF | Adj sum of square | Adj mean square | F value | P value summary | |
|---|---|---|---|---|---|---|
Value | Significant | |||||
Model | 6 | 2248.22 | 374.70 | 67.26 | 0.000 | Model significant |
Linear | 2 | 292.84 | 146.42 | 26.28 | 0.001 | |
Citric acid | 1 | 236.05 | 236.05 | 42.37 | 0.000 | |
Effersoda | 1 | 56.78 | 56.78 | 10.19 | 0.015 | |
Square | 2 | 1851.88 | 925.94 | 166.20 | 0.000 | |
Citric acid (mg)*citric acid (mg) | 1 | 782.17 | 782.17 | 140.40 | 0.000 | |
Effersoda*effersoda | 1 | 1208.32 | 1208.32 | 216.89 | 0.000 | |
2-way interaction | 1 | 100.00 | 100.00 | 17.95 | 0.004 | |
Citric acid (mg)*effersoda | 1 | 100.00 | 100.00 | 17.95 | 0.004 | |
Lack-of-fit | 3 | 8.33 | 2.78 | 0.36 | 0.785 | Lack-of-fit not significant |
Model summary | ||||||
S | R-sq | R-sq (adj) | R-sq (pred) | |||
2.36032 | 98.92% | 96.83% | 94.00% | |||