Today’s Guest Post comes from Coleman R. Rich, who is Chair of Elon University’s Marketing and Entrepreneurship Department. Coleman is also Senior Lecturer in Operations and Supply Chain Management.
I used many quality tools in the textile industry before coming to academia and I wanted to create an exercise where students could understand the use of two common tools, the check sheet and the Pareto chart.
Here are the items needed: Blank check sheet, Graph paper, paper plates, and a 1.69 oz bag of M&M’s for each student.
Instructions: I tell the students they are finished goods inspectors and each color of M&M is a defect. They are to count the number of defects using tick marks and record that information on their check sheet. Then they are to rank each color from high number of occurrences to the lowest number of occurrences and calculate the cumulative percent. From this information, draw a Pareto Chart of the colors on the graph paper and correctly label the chart.
Discussion: After the exercise, I call on students to tell me the number of blue, green, orange, etc. defects in their bag and the total number of M&M’s in their bag. I record this information on the board for the class to see the randomness of the different colors in each bag. I focus on the total number of M&M’s in each bag which you’ll see will vary between 63 and 57 M&M’s per bag. This leads to a discussion of variation and SPC. I also discuss what is Critical to Quality to the manufacturer and the Consumer. Finally I have the students visually inspect the M&M’s for chips, cracks, shapes, etc., and ask why the Mars company doesn’t try to create a perfect M&M. I think you know the answer to that.
Dr. Matt Valle, Professor of Management, here at Elon University has taken this exercise a step further using other quality tools in our paper, “Quality Tools for Project Management: A Classroom Exercise” to be published in Business Education Innovation Journal, Vol. 4, No. 2, December 2012.