Question: Consumer Reports provided overall customer satisfaction scores for AT&T. Sprint. T-Mobile, and Verizon cell-phone services in major metropolitan areas throughout the United States. The rating for each service reflects the overall customer satisfaction considering a variety of factors such as cost. connectivity problems. dropped calls. static interference, and customer support. A satisfaction scale from 0 to 100 was used, with 0 indicating completely dissatisfied and 100 indicating completely satisfied. The rating for the four cell-phone services in 20 metropolitan areas as shown (Consumer Reports, January 2009).
a. Consider T-Mobile first. What is the median rating?
b. Develop a five-number summary for the T-Mobile service.
c. Are there outliers for T-Mobile? Explain.
d. Repeat parts (b) and (c) for the other three cell-phone services.
e. Show the box plots for the four cell-phone services on one graph. Discuss what a comparison of the box plots tells about the four services. Which service did Consumer Reports recommend as being best in terms of overall customer satisfaction?