A personnel and recruitment company wishes to build a model of likely income level and identifies three factors thought important. Data collected on 20 clients gives the following results (data available on the online platform in file CSE25.xlsx):
a. Find the regression relationship for predicting the income level from the other variables.
b. Assess the statistical quality of this model.
c. Would you expect the company to find the model useful?
d. What other factors would you wish to build into such a model?