a. To determine whether the satisfaction rating of an airline differs between business class and economy class, a survey was performed. Random samples of both groups were asked to rate their satisfaction with the quality of service using the following responses:

Very satisfied

Quite satisfied

Somewhat satisfied

Neither satisfied nor dissatisfied

Somewhat dissatisfied

Quite dissatisfied

Very dissatisfied

Using a 7-6-5-4-3-2-1 coding system, the results were recorded. Can we infer that business and economy class differ in their degree of satisfaction with the service?

b. The responses were recoded using the values 88-67-39-36-25-21-18. Can we infer that business and economy class differ in their degree of satisfaction with the service?

c. What is the effect of changing the codes? Why was this expected?