Question: Happy customers As the Hispanic population in the United States has grown, businesses have tried to understand what Hispanics like. One study interviewed a random sample of customers leaving a bank. Customers were classified as Hispanic if they preferred to be interviewed in Spanish or as Anglo if they preferred English. Each customer rated the importance of several aspects of bank service on a 10-point scale. Here are summary results for the importance of "reliability" (the accuracy of account records and so on):
(a) The distribution of reliability ratings in each group is not Normal. The use of two-sample t procedures is still justified. Why?
(b) Construct and interpret a 95% confidence interval for the difference between the mean ratings of the importance of reliability for Anglo and Hispanic bank customers.
(c) Interpret the 95% confidence level in the context of this study.