Boarding Pain The process of boarding a flight in any airport can be slow and agonizing. Passengers with priority boarding often crowd the gate area, and passengers with carry-on bags jostle for position in line. Because faster boarding time saves airlines money and eases anxiety, airlines are experimenting with more efficient ways to seat passengers and prepare for departure. Consider the following boarding methods.46

DIY Boarding: An electronic scan of each passenger's face removes the need for a passport check. Positive Boarding: Passenger data is used by the airline to send messages directly to travelers concerning gates and times. Cheese Counter Method: Passenger numbers allow one person to board at a time. Alternate Rows: Passengers board in alternate rows, rear to front, and window to aisle. A random sample of similar flights and airplanes using one of these four methods was selected from London's Heathrow Airport. The boarding time (in minutes) for each flight was recorded. Assume the underlying boarding time distributions are continuous.

a. Use the Kruskal-Wallis test with a 5 0.05 to determine whether there is any evidence that at least two of the boarding time populations are different.

b. Find the exact p value for this test.

c. What other statistical test might be appropriate in this case? Check the assumptions and conduct this test. Compare your results with part (a).

d. Which of these boarding methods do you think is the most efficient? Why?