Refer to the real estate data of Example 13.2 that relate the listed selling price y to the square feet of living area 1 x , the number of floors 2 x , the number of bedrooms 3 x , and the number of bathrooms 4 x . The realtor suspects that the square footage of living area is the most important predictor variable and that the other variables might be eliminated from the model without loss of much prediction information. Test this claim with a =.05.