7.24 A producer of computer-aided design software for the aerospace industry receives numerous calls for technical support. Tracking software is used to monitor response and resolution times. In addition, the company surveys customers who request support using the following scale: 0—did not exceed expectations; 1—marginally met expectations; 2—met expectations; 3—exceeded expectations; 4—greatly exceeded expectations. The questions are as follows:
- Q1: Did the support representative explain the process for resolving your problem?
- Q2: Did the support representative keep you informed about the status of progress in resolving your problem?
- Q3: Was the support representative courteous and professional?
- Q4: Was your problem resolved?
- Q5: Was your problem resolved in an acceptable amount of time?
- Q6: Overall, how did you find the service provided by our technical support department?
A final question asks the customer to rate the overall quality of the product using a scale of 0—very poor; 1—poor; 2—good; 3—very good; 4—excellent. A sample of survey responses and associated resolution and response data are provided in the Excel file Customer Support Survey [Attached].
- The company has set a service standard of 1 day for the mean resolution time. Does evidence exist that the response time is more than 1 day? How do the outliers in the data affect your result? What should you do about them?
- Test the hypothesis that the average service index is equal to the average engineer index.
7.35For the data in the Excel file Graduate School Survey, perform a chi-square test for independence to determine if plans to attend graduate school are independent of gender.