Beautiful Visualization

Chapter 4. Color: The Cinderella of Data Visualization

Michael Driscoll

Avoiding catastrophe becomes the first principle in bringing color to information: Above all, do no harm.

—Edward Tufte Envisioning Information Graphics Press

COLOR IS ONE OF THE MOST ABUSED AND NEGLECTED tools in data visualization: we abuse it when we make poor color choices, and we neglect it when we rely on poor software defaults. Yet despite its historically poor treatment at the hands of engineers and end users alike, if used wisely, color is unrivaled as a visualization tool.

Most of us would think twice before walking outside in fluorescent red Underoos®. If only we were as cautious in choosing colors for infographics! The difference is that few of us design our own clothes, while we must all be our own infographics tailors in order to get colors that fit our purposes (at least until good palettes—like ColorBrewer—become commonplace).

While obsessing about how to implement color on the Dataspora Labs PitchFX viewer, I began with a basic motivating question: why use color in data graphics? We'll consider that question next.

Why Use Color in Data Graphics?

For a simple dataset, a single color is sufficient (even preferable). For example, Figure 4-1 shows a scatterplot of 287 pitches thrown by Major League pitcher Oscar Villarreal in 2008. With just two dimensions of data to describe—the x and y locations in the strike zone—black and white is sufficient. In fact, this scatterplot is a perfectly lossless representation ...