Consider the interaction model $E ( y ) = 7 + 3 x _ { 1 } - 4 x _ { 2 } + 5 x _ { 1 } x _ { 2 }$. Find the slope of the line relating $E ( y )$ and $x _ { 1 }$ when $x _ { 2 } = 2$.
A) 16
B) 10
C) 13
D) 1

Question

Quizplus · Accepted Answer

The slope of the line relating $E(y)$ and $x_1$ when $x_2 = 2$ can be found by differentiating $E(y)$ with respect to $x_1$, which gives $3 + 5x_2$. Substituting $x_2 = 2$ into this expression gives $3 + 5(2) = 13$.

Consider the Interaction Model E(y)=7+3x1−4x2+5x1x2E ( y ) = 7 + 3 x _ { 1 } - 4 x _ { 2 } + 5 x _ { 1 } x _ { 2 }E(y)=7+3x1​−4x2​+5x1​x2​

Consider the Interaction Model $E ( y ) = 7 + 3 x _ { 1 } - 4 x _ { 2 } + 5 x _ { 1 } x _ { 2 }$