Final answer:
The predicted difference in college GPA between student B, who has a 0.2 points higher high school GPA and a 3 points lower ACT score than student A, is 0.09 points.
Step-by-step explanation:
The question requires the calculation of the predicted difference in college GPA between two students (student B and student A) based on the provided model and parameter estimates. According to the given regression equation colGPA = β1 + β2*hSGPA + β3*ACT + u, and the parameter estimates β1 = 0.5, β2 = 0.6, and β3 = 0.01. Assuming student B has a 0.2 points higher high school GPA (hSGPA) and a 3 points lower ACT score than student A, the predicted difference in their college GPAs is calculated as:
- Difference in hSGPA component = β2 * (hSGPA_B - hSGPA_A) = 0.6 * (hSGPA_A + 0.2 - hSGPA_A) = 0.6 * 0.2 = 0.12
- Difference in ACT component = β3 * (ACT_B - ACT_A) = 0.01 * (ACT_A - 3 - ACT_A) = -0.01 * 3 = -0.03
- Total predicted difference colGPA_B - colGPA_A = Difference in hSGPA component + Difference in ACT component = 0.12 - 0.03 = 0.09
So the predicted difference in college GPA between student B and student A is 0.09.
1