The Lottaburger restaurant chain in central New Mexico is conducting an analysis of its restaurants, which take pride in serving burgers and fries to go faster than the competition. As a part of its analysis, Lottaburger wants to determine if its speed of service is different across its four outlets. Orders at Lottaburger restaurants are tracked electronically, and the chain is able to determine the speed with which every order is filled. The chain decided to randomly sample 20 orders from each of the four restaurants it operates. The speed of service for each randomly sampled order was noted and is contained in the file Lottaburger.
a. At the α = 0.05 level of service, can Lottaburger conclude that the speed of service is different across the four restaurants in the chain?
b. If the chain concludes that there is a difference in speed of service, is there a particular restaurant the chain should focus its attention on? Use the appropriate test for multiple comparisons to support your decision. Use α = 0.05.