Use a bubble plot to explore the relationships among three variables on a single plot. Like a scatterplot, a bubble plot plots a y-variable versus an x-variable. However, the symbols (also called bubbles) on the bubble plot vary in size. The area of each bubble represents the value of a third variable.

You work in a car dealership. Your customers want a convenient way to compare the fuel economy (measured in miles per gallon, or MPG) and the cost of each vehicle. You decide to create a bubble plot to summarize fuel economy and cost.

Data: BubblePlot.MTW (available in the Sample Data folder).