Answer the following question in full details.
A national job placement company is interested in developing a model that might be used to explain the variation in starting salaries for college graduates based on the college GPA. The following data were collected through a random sample of the clients with which this company has been associated.
| GPA |
Starting Salary
|
| 3.20 |
$35,000
|
| 3.40 |
$29,500
|
| 2.90 |
$30,000
|
| 3.60 |
$36,400
|
| 2.80 |
$31,500
|
| 2.50 |
$29,000
|
| 3.00 |
$33,200
|
| 3.60 |
$37,600
|
| 2.90 |
$32,000
|
| 3.50 |
$36,000
|
Based on this sample information answer the following questions:
a. Determine the least squares regression model?
b. Determine what percent of the variation in starting salaries is explained by GPA?
c. Test to determine whether the regression model is statistically significant at the 0.05 level of significance?
d. Develop a scatter plot of the data and locate the regression line on the scatter plot?
e. Use the regression equation to determine the predicted values of y.
f. Use the predicted and actual values of y to calculate the residuals.
g. Plot the residuals against the predicted values of y. What does the graph tell you?