Suppose you estimate the sample regression function $$ Midt\widehat {erm ~Sc}ore = 62.33 + 4.62 \cdot \text { Time Taken } - 0.038 \cdot \text { Time Taken } { } ^ { 2 }$$
You should conclude that the marginal effect of time taken on midterm score is
A)4.62.
B)-0.038.
C)4.62 - 0.038.
D)4.62 - 0.076 ∙ Time Taken.

Question

Suppose you estimate the sample regression function $$  Midt\widehat {erm ~Sc}ore = 62.33 + 4.62 \cdot \text { Time Taken } - 0.038 \cdot \text { Time Taken } { } ^ { 2 }$$
You should conclude that the marginal effect of time taken on midterm score is
A)4.62.
B)-0.038.
C)4.62 - 0.038.
D)4.62 - 0.076 ∙ Time Taken.

Quizplus · Accepted Answer

The marginal effect of time taken on midterm score in a quadratic equation like this is given by taking the derivative of the score with respect to time taken, which results in $4.62 - 0.076 \cdot \text{Time Taken}$.

Suppose You Estimate the Sample Regression Function Midterm Sc^ore=62.33+4.62⋅ Time Taken −0.038⋅ Time Taken 2 Midt\widehat {erm ~Sc}ore = 62.33 + 4.62 \cdot \text { Time Taken } - 0.038 \cdot \text { Time Taken } { } ^ { 2 }Midterm Score=62.33+4.62⋅ Time Taken −0.038⋅ Time Taken 2

Suppose You Estimate the Sample Regression Function $Midt\widehat {erm ~Sc}ore = 62.33 + 4.62 \cdot \text { Time Taken } - 0.038 \cdot \text { Time Taken } { } ^ { 2 }$