Source

Sum of squares

df

Mean square

F value

p-value

Prob > F

Model

951.28

14

67.95

11.87

<0.0001

X₁

197.32

1

197.32

34.46

<0.0001

X₂

45.12

1

45.12

7.88

0.0140

X₃

59.59

1

59.59

10.41

0.0061

X₄

1.33

1

1.33

0.23

0.6377

X₁ * X₂

28.25

1

28.25

4.93

0.0433

X₁ * X₃

12.96

1

12.96

2.26

0.1547

X₁ * X₄

2.61

1

2.61

0.46

0.5107

X₂ * X₃

25.91

1

25.91

4.52

0.0517

X₂ * X₄

14.67

1

14.67

2.56

0.1318

X₃ * X₄

35.28

1

35.28

6.16

0.0264

$X_1^2$

273.51

1

273.51

47.77

<0.0001

$X_2^2$

276.15

1

276.15

48.23

<0.0001

$X_3^2$

104.49

1

104.49

18.25

0.0008

$X_4^2$

144.65

1

144.65

25.26

0.0002

Residual

80.16

14

5.73

Lack of Fit

78.23

10

7.82

16.15

0.0082

Pure Error

1.94

4

0.48

Cor Total

1031.44

28