MGT 301
Practice Assignment – SPC Mini-Case Response
Allison Jon, the manager of an 800-number reservation service for a nationwide chain of luxury
hotels, is concerned about the productivity of her operation. Analysis of past data shows that it
should take an average of five minutes to properly process a reservation. To setup a control chart
for reservation service time, Allison records the time it takes to complete the reservation. She
randomly samples 5 reservations every day for 30 days.
Set up the appropriate control charts for these 30 days of data. Data File in BbLearn. Plot the data
for these 30 days in an xbar chart and an r chart.
Now monitor the process. Ten days of data have been collected since creating the control charts.
A second 10 days of data have been collected.
Questions:
1) Comment about the control limits. What are control limits? Are the control limits you set
appropriate? Explain.
Looking at the control limits it helps determine whether a company is doing good or
there is error either in production or material to management. You can see looking at
the first 10 days X-bar chart compared to the second that the first is out of control by
looking at each dot how far it is is compared to the second 10 days that are in
control.
2) Comment on the reservation process in the first 10 days of monitoring. If the control chart
