Variable

Estimate

Std. Error

t-value

Pr (>|t|)

C

27.04466

175.9025

0.153748

0.8784

X1^2

−0.110573

0.199299

−0.554810

0.5814

X1*X2

0.289404

0.215308

1.344139

0.1849

X1*X3

−0.338914

0.301625

−1.123628

0.2664

X1*X4

−0.232366

0.232549

−0.999213

0.3224

X1*X6

−0.044353

0.039873

−1.112343

0.2712

X1

6.776101

7.249776

0.934663

0.3544

X2^2

−0.062041

0.074980

−0.827436

0.4118

X2*X3

−0.068328

0.223471

−0.305757

0.7610

X2*X4

0.138883

0.187077

0.742384

0.4613

X2*X6

−0.012555

0.029427

−0.426653

0.6714

X2

−4.001684

5.751358

−0.695781

0.4897

X3^2

0.086175

0.265767

0.324250

0.7471

X3*X4

0.371117

0.349468

1.061948

0.2933

X3*X6

0.044668

0.072411

0.616876

0.5401

X3

−4.729345

12.04327

−0.392696

0.6962

X4^2

−0.143504

0.116760

−1.229052

0.2247

X4*X6

−0.027806

0.044096

−0.630572

0.5311

X4

4.784077

8.236844

0.580814

0.5639

X6^2

0.023550

0.007464

3.155170

0.0027

X6

−1.455804

2.161876

−0.673399

0.5037

R-squared

0.632185

Mean dependent var

11.73660

Adjusted R-squared

0.487944

S.D. dependent var

22.22738

S.E. of regression

15.90548

Akaike info criterion

8.609698

Sum squared resid

12902.20

Schwarz criterion

9.273725

Log likelihood

−288.9491

Hannan-Quinn criter.

8.874049

F-statistic

4.382839

Durbin-Watson stat

2.419165

Prob (F-statistic)

0.000010