Displaying Categorical Data (Lesson 1.2)
Chapter 1 - Day 2
Compare distributions of categorical data with bar charts.
Identify what makes some graphs of categorical data deceptive.
Make and interpret bar charts (or pie charts) of categorical data.
Let students have a short discussion about question #1 and then make a list of social media apps on the whiteboard. Then students will come to the board to vote for their favorite. Use the data to create a frequency table and a relative frequency table (from Lesson 1.1).
This is the first lesson of many where students will be using the applets found at www.stapplet.com. These applets were designed specifically for this course and this textbook and students can access them on any device (laptop, Chromebook, Ipad, phone). In order to help them choose the right applet, ask them if the variable we are recording is categorical or quantitative (favorite social media app is categorical) and whether there is a single group or multiple groups (the data is just for our class, so single group). We suggest running this entire Intro Stats class without a calculator. After all, graphing calculators are the new slide rule.
When discussing the bar chart, be sure to point out that the bars have space between them. In Lesson 1.5, students will be making histograms, which also have bars, but with no space between them. The difference is that bar graphs are used for categorical data and histograms are used for quantitative data.
The final learning target is about misleading graphs and is not covered in the activity. Be sure to explain during the QuickNotes and then consider showing students some examples (which can be found here or here).