Visual Intelligence: Microsoft Tools and Techniques for Visualizing Data

Chapter 12

Comparison Visuals

Using a visualization to compare two or more objects either at a point in time or over a period is one of the oldest forms of visualization. In Chapter 11, a treatment of comparisons over time has been done, so this chapter focuses on point-in-time comparisons.

Comparing items of data and deciding which is better is one of the most common actions people take. This may take the form of ranking: for instance determining which of your stores are in the top 10% and which stores are in the bottom 10% by sales (or gross profit) allows you to determine the appropriate remedial action for the poorly performing stores, and apply what’s been learned by the best 10% to your other stores.

Another comparison is comparing actuals against targets: For instance, while a store may be in the top 10% by sales, it could well have not achieved a target set for the period.

In this chapter you learn about several methods for comparing values visually: heatmaps (also called chloropleths), traditional bar charts, and pie charts, as well as bullet graphs, radar graphs, and matrices.

Overview of Point-in-Time Comparisons

The effect used to show point-in-time comparisons can take one or a combination of the following forms:

• Change in color (heatmaps, chloropleth, indicators)
• Change in width (bar charts)
• Change in height (column charts, prism charts)
• Change in position (scatter plots)
• Change in area (bubble charts, tree maps)
• Change in angular width (pie charts, donut charts) ...