Term

Coefficient

Standard Error

Students’ t test

Probability > |t|

Intercept

101.09

1.01

99.86

<0.0001

X₁

0.87

0.62

1.40

0.2212

X₂

0.59

0.62

0.95

0.3868

X₃

3.50

0.62

5.64

0.0024

X₁X₂

−0.95

0.88

−1.08

0.3280

X₁X₃

0.38

0.88

0.44

0.6808

X₂X₃

0.83

0.88

0.94

0.3899

X₁²

1.25

0.91

1.37

0.2292

X₂²

0.66

0.91

0.72

0.5037

X₃²

1.02

0.91

1.12

0.3125