Concept explainers
Recall that in exercise 44, the admissions officer for Clearwater College developed the following estimated regression equation relating final college GPA to the student’s SAT mathematics score and high-school GPA.
where
x1 = high-school grade point average
x2 = SAT mathematics score
y = final college grade point average
A portion of the Excel Regression tool output follows.
- a. Complete the missing entries in this output.
- b. Using α = .05, test for overall significance.
- c. Did the estimated regression equation provide a good fit to the data? Explain.
- d. Use the t test and α = .05 to test H0: β1 = 0 and H0: β2 = 0.
44. 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 high-school GPA.
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.
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Chapter 15 Solutions
Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card)
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