Table 5 The application of regression and ANOVA tests for fluoride removal
Variables | Coefficients symbol | Coefficients | Standard error | t Stat | p-value |
|---|---|---|---|---|---|
Intercept | b0 | 64.70 | 7.32 | 8.83 | 3.73E−08 |
X1 | b1 | 12.21 | 5.40 | 2.26 | 0.036 |
X2 | b2 | − 3.37 | 0.75 | − 4.49 | 0.000 |
X3 | b3 | − 0.05 | 0.08 | − 0.56 | 0.580 |
X1X2 | b4 | − 0.03 | 0.20 | − 0.13 | 0.897 |
X1X3 | b5 | − 0.04 | 0.07 | − 0.67 | 0.513 |
X2X3 | b6 | 0.01 | 0.01 | 1.02 | 0.319 |
X1X2X3 | b7 | − 0.02 | 0.01 | − 0.38 | 0.711 |
Regression statistics | Multiple R | R square | Adjusted R square | Standard error | Observations |
|---|---|---|---|---|---|
0.96 | 0.92 | 0.89 | 2.99 | 27 |
ANOVA | df | SS | MS | F | Significance F |
|---|---|---|---|---|---|
Regression | 7 | 1965.85 | 280.84 | 31.49 | 3.71E−09 |
Residual | 19 | 169.43 | 8.92 | ||
Total | 26 | 2135.28 |