Students are often intimidated by the practical application of the chi-square test, primarily because of the complex process used to conduct the analysis. However, once familiar with the procedure, you will notice that the technique can be a valuable tool for managers.

Consider the following scenario which would be an example of utilizing chi-square for quality control purposes:

Lets suppose that you work in the quality control department for the M&Ms/Mars Company. You have been tasked with reviewing product consistency regarding the packaging of plain M&Ms candy. Your job is to determine if the number of blue, green, brown, orange, and yellow M&Ms in each bag is relatively equal. Obviously, not every bag will contain the exact same number of M&Ms, divided into equal quantities. However, as part of your quality control responsibilities you want to determine if there is a significant difference in the number of colors in each bag. After all, you dont want customers to open a bag and only receive primarily one or two colors. You could use a one variable chi-square test to analyze your research question: is the number of blue, green, brown, orange, and yellow M&Ms significantly different?

Your stated null and alternative hypotheses would look like this:

Ho: There is no significant difference between the number of blue, green, brown, orange, and yellow M&Ms per bag.

H1: There is a significant difference between the number of blue, green, brown, orange, and yellow M&Ms per bag.

Next, we would move through the steps required to complete the chi-square test.

Class: How would you conduct this analysis? What are the steps that we must follow?