Table 7.

Results of the regression analysis of the CCD

Source	Coefficient	SE	t-test	P>|t|
Interception	13958	205.7	67.868	0.000
x1	−430	136.5	−3.147	0.010
x2	−449	136.5	−3.288	0.008
x3	124	136.5	0.910	0.384
x12	−1179	133.1	−8.864	0.000
x22	−291	133.1	−2.183	0.054
x32	−149	133.1	−1.121	0.288
x1x2	−701	178.3	−3.930	0.003
x1x3	92	178.3	0.517	0.616
x2x3	−210	178.3	−1.179	0.266