Designing visualization is not a simple case of picking one from the list that a tool supports. The right visualization conveys the right message, whereas the wrong visualization might confuse the message you are trying to send, or even convey the wrong message. An example of this is a 3D pie chart in which the 3D distortion shows one slice of a pie as the largest even though it isn’t the biggest piece. Another example is a line chart that shows discrete values, such as murder rates, across countries but the interpolation between the countries makes no sense. Each visualization is covered in later chapters; this chapter shares the background of why you should choose different visualizations.
The goal of a visualization is to make it possible to answer questions—even questions you didn’t know you should be asking until you saw the pattern of the data in the visualization.
Example questions include:
Temporal analysis is the place where the advantages of visualization first become easily apparent. Someone reading two lines on a graph can predict where the lines will cross or diverge by glancing at the graph. (Read more in Chapter 11.)
Visualizations answer questions by highlighting patterns and outliers. For example, changing the color of an element ...