The Department of Motor Vehicles wanted to understand and better control the waiting time of customers of the drivers license office. To do this, they constructed X-bar and R-charts by sampling the waiting times of the first five customers at the beginning of each shift (7 a.m., 12 p.m., and 3 p.m.). How might the sampling process be improved, and what would you recommend?
Suppose that you were monitoring the time it takes to complete order transactions at a call center. Discuss what might cause such out-of-control conditions as a trend, shift in the mean, or cycles in an x-bar chart in this situation.
Remember to show all work and to answer all parts of the questions. The work must be submitted in a Word or Excel document