5b: MacDonald Case Study (60%)

You are the McDonald's Project team for this area. In an effort to increase customer satisfaction and capture more market share, you performed customer surveys/satisfaction analysis.

Through your thorough analysis, you found service time to be a major factor. You have also broken service time into two parts:

• wait time in line
• order time (time from when you begin to order your food until you are given your food and change)

Your first efforts will focus on order time. You have a hunch that order time may differ for drive-thru versus counter service and for ordering by numbers versus off menu. Two classes of Six Sigma trainees were sent out for lunch, half to the Miami Lakes McDonald's and half to Miami Gardens. About half of the people were asked to order at the drive-thru and half at the counter. The following data was collected:

• Order Time [seconds]
• Location [1 Miami Lakes, 2 Miami Gardens]
• Service [1 Drive-thru, 2 Counter]
• Order Method[1 By Number, 2 Off Menu]

To determine what the performance standard should be, you surveyed 100 customers, asking them: "To ensure repeat business, how much time are you willing to spend from when you start to order your food until you are given your food and change?" Based on these results, you determined the performance standard for order time to be 90 seconds.

Instructions

• Minitab file:Yield.mwx contains the McDonald's data.
• Hint for comparing the data subgrouped by 1 factor: you will first have to sort the data by time of day, and then unstack it. For instance, unstacking by location will result in two columns, one for Miami Lakes and one for Miami Gardens. This enables you to do the Run Charts and Histograms.
• Answer the following questions about the McDonald's data.

1. Visualize the distribution of the data. (5 points)

2. Visualize differences between average service time and between service time variation. (5 points)

3. Are there any non-random patterns over time? (5 points)

4. Is the data normally distributed? (5 points)

5. Do the two groups have the same consistency in speed of service? (5 points)

6. Is there a statistically significant difference between the average speed of service? (5 points)