Refer to the Journal of Engineering for Gas Turbines and Power (Jan. 2005) study of gas turbines augmented with high-pressure inlet fogging, Exercise 8.39. Heat rate data (kilojoules per kilowatt per hour) for each of three types of gas turbines (advanced, aero derivative, traditional) are saved in the GASTURBINE file. In order to compare the mean heat rates of two types of gas turbines, you assumed that the heat rate variances were equal.

a. Conduct a test (at α = .05) for equality of heat rate variances for traditional and aero derivative augmented gas turbines. Use the result to make a statement about the validity of the inference derived in Exercise 8.33 a.

b. Conduct a test (at α = .05) for equality of heat rate variances for advanced and aero derivative augmented gas turbines. Use the result to make a statement about the validity of the inference derived in Exercise 8.39 b.

Data from Exercise 8.39

Refer to the Journal of Engineering for Gas Turbines and Power (Jan. 2005) study of gas turbines augmented with high-pressure inlet fogging, Exercise 8.29. The researchers classified gas turbines into three categories: traditional, advanced, and aero derivative. Summary statistics on heat rate (kilojoules per kilowatt per hour) for each of the three types of gas turbines in the sample are shown in the MINITAB printout.