Lesson 2.1 – Relationships between Two Categorical Variables

• Distinguish between explanatory and response variables for categorical data.
• Make a segmented bar chart to display the relationship between categorical variables.
• Determine if there is an association between two categorical variables and describe the association if it exists.

This chapter we are trying to keep our context as consistent as possible.  We spent the previous class hour connecting data during the Barbie Bungee.  We will be using this data as often as we can throughout the chapter.  At the end of the chapter, groups will be using all the tools they learned to create the best possible regression to predict the number of rubber bands that Barbie will need for her bungee jump.

Activity: What was your favorite toy as a child?

Our Barbie data wouldn’t work for this lesson since we needed to collect two categorical variables, so instead we collected data from the students on gender and favorite toy when they were young.  After collecting data, the groups entered it into the applet to create a segmented bar chart.

Notes

We didn’t have the students create the graphs by hand because it can be pretty tedious.  However, looking back now it may have been helpful.  The students have a good understanding of how to look for association between variables using a segmented bar chart, but they still have a little bit of an issue reading them accurately.