Lovell Levelers just reported that Specific Motors is a satisfied customer. The leveler plate quality is no longer an issue. In fact, they have not seen a single defect in six months! Phyllis Kendall made another surprise visit, but this time for a more pleasant reason. She presented each member of the team with a crisp, new $100 bill as a show of appreciation. But she also pointed out that we need to have a way to ensure that this problem will not crop us again. The team is one step ahead of her and explained that the thickness of the leveler plates is being monitored and controlled with an on-going XMR (Individuals and Moving Range) chart so that any assignable causes of variation will be detected and addressed quickly. The parameters affecting the product thickness are also being monitored with a capability study.

Instructions: We want to make sure you can calculate control limits. You may construct the control chart by hand, or you may use a charting function in Excel.

Thickness data for XMR control chart below:

0.551

0.552

0.547

0.548

0.547

0.547

0.538

0.546

0.558

0.543

0.545

0.547

0.556

0.548

0.545

0.552

0.549

0.546

0.545

0.553

0.549

0.558

0.542

0.557

0.546

Answer the following: Use 4 decimal places for your answer

1. Calculated average moving rate?_________________
2. Upper control limit for the moving rate ______________
3. Upper control limit for the individual _________________
4. Lower control limit for t he individual _________________
5. Is there adequate discrimination? Explain your answer.
6. Which chart did you use and exactly how many strata are there on that chart? How may should there be?
7. Is this process stable? Explain your answer.