In: Statistics and Probability
as the measure of five-year owner costs. Road-test scores are the results of more than 50 tests and evaluations and are based upon a 100-point scale, with higher scores indicating better performance, comfort, convenience, and fuel economy. The highest road-test score obtained in the tests conducted by Consumer Reports was a 99 for a Lexus LS 460L. Predicted-reliability ratings (1 = Poor, 2 = Fair, 3 = Good, 4 = Very Good, and 5 = Excellent) are based on data from Consumer Reports’ Annual Auto Survey. A car with a value score of 1.0 is considered to be “average-value.” A car with a value score of 2.0 is considered to be twice as good a value as a car with a value score of 1.0; a car with a value score of .5 is considered half as good as average; and so on. The data for 20 family sedans, including the price ($) of each car tested, follow.
The summary statistics is:
The regression equation:
Value score= 1.24 – 2.061 cost/mile + 0.01 Road test score + 0.167 predicted reliability – 0.017Family sedan
With an R square equal to 93.31%.