Concept explainers
The admissions officer for Clearwater College developed the following estimated regression equation relating the final college GPA to the student’s SAT mathematics score and highschool GPA.
ŷ = −1.41 + .0235x1 + .00486x2
where
x1 = high-school grade point average
x2 = SAT mathematics score
y = final college grade point average
- a. Interpret the coefficients in this estimated regression equation.
- b. Predict the final college GPA for a student who has a high-school average of 84 and a score of 540 on the SAT mathematics test.
a.
Interpret the coefficients in the estimated regression equation.
Explanation of Solution
Calculation:
The estimated regression equation relating the final GPA to the student’s SAT mathematics score and high school is GPA is
Multiple linear regression model:
A multiple linear regression model is given as
Slope in a multiple regression equation:
The slope
The ‘Coefficient’ column of the regression analysis output gives the slopes corresponding to the respective variables stored in the column ‘Variable’.
The coefficient or slope of
The interpretation of the coefficient
The coefficient or slope of
The interpretation of the coefficient
b.
Predict final college GPA for a student who has a high-school average of 84 and a score of 540 on the SAT mathematical test.
Answer to Problem 44SE
The predicted final college GPA for a student who has a high-school average of 84 and a score of 540 on the SAT mathematical test is 3.19.
Explanation of Solution
Calculation:
The high school average of 84 implies that,
The regression equation is
For
Thus, the predictedfinal college GPA for a student who has a high-school average of 84 and a score of 540 on the SAT mathematical test is 3.19.
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Chapter 15 Solutions
Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card) (MindTap Course List)
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