Consider the interaction model $E ( y ) = 3.6 + 1.2 x _ { 1 } + 2.4 x _ { 2 } + .2 x _ { 1 } x _ { 2 }$. Determine the change in $E ( y )$ when $x _ { 1 }$ is changed from 6 to 7 and $x _ { 2 }$ is held fixed at 3 .
A) $1.8$
B) $4.2$
C) $10.8$
D) $11.4$

Question

Quizplus · Accepted Answer

The change in $E(y)$ due to an increase in $x_1$ from 6 to 7, while $x_2$ is fixed at 3, can be calculated by substituting the values into the interaction term and the $x_1$ term. The change is $1.2 + 0.2 \times 3 = 1.8$.

Consider the Interaction Model E(y)=3.6+1.2x1+2.4x2+.2x1x2E ( y ) = 3.6 + 1.2 x _ { 1 } + 2.4 x _ { 2 } + .2 x _ { 1 } x _ { 2 }E(y)=3.6+1.2x1​+2.4x2​+.2x1​x2​

Consider the Interaction Model $E ( y ) = 3.6 + 1.2 x _ { 1 } + 2.4 x _ { 2 } + .2 x _ { 1 } x _ { 2 }$