Pick One: Pretty or Pretty Misleading #MRX


Look how cool this chart is! The blue, red, and green are neutral and non-offensive. There is no blinding florescence nor strange strobing visual effects. Colours aside, without the scale, obviously a chart no-no, you’re left to your own to determine the size of each slice. Take a minute and decide on the values of the slices yourself. You will probably conclude that the green slice is the smallest, followed by the blue slice, and the red slice is the largest. Want to bet on it?

Here is the exact same pie chart only it’s designed as a 2D chart rather than a 3D chart. Care to change your answer? The green slice, of course, is still the smallest slice. But now, we can see that the red slice and the blue slice are actually identical. Check the 3D pie chart again – you could convince yourself that the red and blue slices are the same but you’re just fooling yourself. If you had used that 3D chart, you would have succeeded in misleading your audience.

Care for another example? Here’s a 3D bar chart that is far less likely to cause confusion. Simply draw a line across the top of the bar to determine the value of each bar. There are even some helpful guidelines to make our work easier for us. The first bar represents 1.7, the second bar represents 3.7, and the third bar represents 5.7. Or does it…?

Again, here is the exact same chart, but drawn as a 2D chart instead as a 3D chart. I swear to you it is the exact same data. But now it appears as though the bars reflect the values 2, 4, and 6. Honest and truly. This is the same data. You’ll just have to try it for yourself to believe it.

3D charts are pretty. They are decorations for boring powerpoint slides or flashy marketing materials. They are not scientific illustrations nor information sharing tools. If you seek to share factual information, stick with 2D. It’s the only option.

cohdra from morguefile

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  • 2 responses

    1. The piece would be more convincing if the comentary around the 3d bar chart had the first value correct. I can’t make it 2.7 however hard I try

      1. You found a typo! Glad you tried so hard. 🙂