Americans Family insurance company wants to design a control chart to monitor whether claim forms are being completed correctly. The company intends to use a control chart to see if the improvements in the design of the form are effective. To start the process the company collected data on the number of incorrectly completed forms over the past 10 days. The insurance company processes thousands of these forms each day, and due to the high cost of inspecting each form, only a small representative sample of 300 was collected each day. The data for the last 10 days are as follows: 10, 8, 9, 13, 7, 7, 6, 11, 12, and 8.
a) What type of control chart(s) should be used?
b) What is the value of central line?
c) Compute the upper and lower control limits for the chart.
d) Based on the data collected, what would you conclude?
e) Do the improvements in the design of the forms effective? What can we say?