Each of 12 undergraduate students has been randomly assigned to one of the 6 cells shown here.

Question:

Each of 12 undergraduate students has been randomly assigned to one of the 6 cells shown here. The purpose of the study is to test whether factor A (if a shopping bag is being carried) and factor B (mode of dress) have main and interactive effects regarding the number of seconds it takes to get waited on at a jewelry counter of an upscale department store. Students have entered the store at times that have been randomly scheduled for the day of the experiment. Using the 0.025 level of significance in testing for the main and interactive effects, what conclusions should be drawn from this experiment? Determine the 95% confidence interval for the population mean for each factor level. (Use data file XR12077.)