Term

Effect value

Standard error

t-value (2 DF)

p-value

Average

1.63

0.020

80.2

<0.01

X1

0.12

0.012

10.0

<0.01

X12

-0.12

0.015

-8.4

0.01

X5

0.14

0.012

11.4

<0.01

X52

-0.17

0.015

-11.8

<0.01

X1.X5

-0.06

0.018

-3.3

0.08

t- tabulated = ±2.92 for a 90 % confidence level and 2 DF.
Table 6: Coefficient regression values and respective significance tests.