One of the major measures of the quality of service provided by any organization is the speed with which it responds to customer complaints. A large family-held department store selling furniture and...

One of the major measures of the quality of service provided by any organization is the speed with which it responds to customer complaints. A large family-held department store selling furniture and flooring, including carpet, had undergone a major expansion in the past several years. In particular, the flooring department had expanded from 2 installation crews to an installation supervisor, a measurer, and 15 installation crews. Last year, there were 50 complaints concerning carpet installation. The following data, in the file furniture.xls, represent the number of days between the receipt of a complaint and the resolution of the complaint:

a. Construct a 95% confidence interval estimate of the mean number of days between the receipt of a complaint and the resolution of the complaint.

b. What assumption must you make about the population distribution in (a)?

c. Do you think that the assumption made in (b) is seriously violated? Explain.

d. What effect might your conclusion in (c) have on the validity of the results in (a)?