Tuesday, July 9, 2019

A mosaic plot that exemplifies good design practices

Bloomberg's Lauren Leatherby and Chris Martin visualize energy consumption per country, and their reliance on coal, natural gas, petroleum, nuclear, and renewable sources. The result is an interactive mosaic plot (also known as “Marimekko chart”) that reveals plenty of insights, such as the rise of China and India, or the meager increase of renewables since 1980.

This visualization exemplifies a few interactive design good practices. For instance, if you search for a country, a black outline appears in front of it. This outline remains visible while you play with the time slider, allowing you to focus on that country. Here's Japan:

Moreover, when you hover over any country, a time-series stacked area graph appears, so this visualization also applies a principle described in The Truthful Art, and that I also explain to the general public in How Charts Lie: when a topic is complex, we can't expect that a single visualization will suffice; instead, we may need to encode the same data in multiple ways, as each of them may yield different patterns or trends.

Bloomberg's mosaic plot is part of a long story that showcases other charts, and that discusses how energy production and consumption have varied in several countries in the past few decades. Don't miss it.