# Table 2 ANOVA for quadratic model

Source

DF

Seq SS

F value

p value

Regression

14

3685.87

3685.87

263.28

77.1

0

Linear

4

778.17

778.17

194.54

56.97

0

X1

1

587.02

587.02

587.02

171.9

0

X2

1

120.4

120.4

120.4

35.26

0

X3

1

65.19

65.19

65.19

19.09

0.001

X4

1

5.56

5.56

5.56

1.63

0.223

Square

4

2179.18

2179.18

544.79

159.54

0

X1Â *Â X1

1

158.66

0.58

0.58

0.17

0.685

X2Â *Â X2

1

1106.41

1532.83

1532.83

448.87

0

X3Â *Â X3

1

698.9

825.68

825.68

241.79

0

X4Â *Â X4

1

215.2

215.2

215.2

63.02

0

Interaction

6

728.52

728.52

121.42

35.56

0

X1Â *Â X2

1

12.53

12.53

12.53

3.67

0.076

X1Â *Â X3

1

350.25

350.25

350.25

102.57

0

X1Â *Â X4

1

359.1

359.1

359.1

105.16

0

X2Â *Â X3

1

0.02

0.02

0.02

0.01

0.936

X2Â *Â X4

1

3.22

3.22

3.22

0.94

0.348

X3Â *Â X4

1

3.39

3.39

3.39

0.99

0.336

Residual error

14

47.81

47.81

3.41

Â Â

Lack-of-fit

10

33.28

33.28

3.33

0.92

0.588

Pure error

4

14.53

14.53

3.63

Â Â

Total

28

3733.67

Â Â Â Â
1. DFâ€‰=â€‰Degree of freedom; Seq SSâ€‰=â€‰sequential sum of square; Adj SSâ€‰=â€‰adjusted sum of square; Adj MSâ€‰=â€‰adjusted mean square; Fâ€‰=â€‰variance ratio (Fisher F-value); pâ€‰=â€‰probability value