Crime taxonomy · Drawing and geometry

Area, volume or 3D distortion

Scaling icons, bubbles or 3D shapes so a doubling looks like a quadrupling.

What it looks like

A one-dimensional value is shown by a shape whose width and height (or volume) are both scaled, or by 3D perspective that makes nearer slices and bars look bigger.

Example

3D DISTORTION

FIXED

Why it is bad

• Double the side of a square and its area quadruples. Readers judge area, not side length.
• 3D perspective makes the slice or bar closest to the viewer look larger than its value.
• Pictograms feel friendly and harmless, which makes the exaggeration easy to miss.

How to fix it

1. Use length (bars, dots on a common scale) for single values.
2. If you use bubbles or icons, scale their area, not their radius or height.
3. Drop 3D effects. They add no information and always distort.