In a multiple regression model $y ^ { \prime } = - 9 + 3 x _ { 1 } + 21 x _ { 2 } + 13 x _ { 3 } + 4 x _ { 4 }$, if the $x _ { 1 }$ value changes by 2 , then the predicted value for $y$ will change by
A) 32
B) 6
C) -3
D) 42

Question

Quizplus · Accepted Answer

The coefficient of $x_1$ is 3, indicating that for every unit increase in $x_1$, $y'$ increases by 3. Therefore, if $x_1$ changes by 2, $y'$ changes by $2 \times 3 = 6$.

In a Multiple Regression Model y′=−9+3x1+21x2+13x3+4x4y ^ { \prime } = - 9 + 3 x _ { 1 } + 21 x _ { 2 } + 13 x _ { 3 } + 4 x _ { 4 }y′=−9+3x1​+21x2​+13x3​+4x4​

In a Multiple Regression Model $y ^ { \prime } = - 9 + 3 x _ { 1 } + 21 x _ { 2 } + 13 x _ { 3 } + 4 x _ { 4 }$