Bar Graphs, Pie Charts, and more

 The first thing we will discuss is the area principle, which basically states that each unit in our sample should be equally represented with area on a graph. This way, we can see that a larger area means more units in that category.

 A bar chart is a graphical representation of categorical data.  We will discuss both a basic bar chart and a segmented bar chart.  For a basic bar chart, the x-axis is the categories for your variable, and the y-axis is either the frequency, or relative frequency.  See the video for a detailed look at making a bar chart.

 For a basic bar chart, you can only use one variable. We get this information from a frequency distribution. But for a segmented bar chart, you can use two variables. This is what is used for a contingency table.  Please refer to the second video for a detailed explanation of making a segmented bar chart.

 The third graph discussed in this powerpoint is a pie chart.  This is represented by a circle, marked off by lines radiating from the center of the circle.  Each piece of the pie represents a category.  The second video shows you how to make a pie chart.

 Make sure you give every chart a title and axis label.  This ensures that whoever is looking at your graph can understand it without having to reference anything else.