Question

Research into the relationship between hours of study and grades shows widely different conclusions. A recent survey of graduates who wrote the Graduate Management Admissions Test (GMAT) had the following results.       

Hours

Studied            Average

(Midpoint)      Score

40                    210

50                    300

65                    345

75                    455

85                    540

105                  660

95                    700

           

1. Run the regression analysis in Excel on this data. Include your output with your answer. (Note: You may calculate by hand if you prefer).
2. What is the regression equation for this relationship?
3. Use the regression equation to predict the average score for each category of hours studied.
4. Plot the original data and the regression line on a scattergram. (You may use Excel).
5. How accurate is this regression at predicting GMAT scores based on hours studied? Explain.
6. Use the t statistic to determine whether the Correlation Coefficient is “significant” at the 95% confidence level.

Answer 1

I have answered the question using computer package look at images carefully all the parts are anwerd.

Predicted column in last picture is your answer for part c.

part d has been answered above the plot ans line is there.

part e and f are in the last image.

part a and b are in the first 2 images.