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This is how misunderstanding pie charts led to them being hated
The importance of choosing the right chart for your goal.
The pie chart is one of the most hated charts in all of the visualization, and it became that way because it was misused. They are less accurate than other charts based on the elements of their visualization and should have only be used for niche scenarios. However, because they were used for nearly everything, they’ve garnered a reputation for being ineffective, lazy, and just plain bad.
But pie charts are still useful for certain types of goals, and it highlights the importance of choosing the right chart to answer your questions. Because if you’re not careful, your favorite chart could be next.
The 4 elements of visualizations
According to Nathan Yau’s Data Points: Visualization that means something, 4 elements make up a chart: visual cues, a coordinate system, scale, and context.
Choosing different elements, such as visual cues, is what can turn a bar chart into a column or line chart. However, these visual cues shouldn’t be chosen randomly: different cues are best suited for different types of data.
For example, lines and points can be used when we’re concerned about involves changes over time. But multiple visual cues may be suited towards addressing. For that example of changes over time, it wouldn’t be uncommon for bars to also be a viable option (i.e. creating a bar chart).
So that’s where we have to consider something else: how accurately our users can perceive these visual cues.
Accurately perceiving visual cues
In 1985, William Cleveland and Robert McGill conducted a study on graphical perception to understand how accurately people perceive visual cues. This resulted in this sort of ranking system of how accurately people not only…
