Chapter 4 of 10All chapters
Chapter 4 of 10
Axes and scales
Where distortion enters.
Zero or not
Bar length encodes value, so bars must start at zero. Lines encode position over time, so a truncated axis can be honest if it is clearly labelled.
- Truncating a bar axis exaggerates differences dramatically.
- Say when an axis is truncated rather than hoping nobody checks.
Log scales
A logarithmic axis suits data spanning orders of magnitude and equal proportional changes. It must be labelled clearly, because most readers will assume linear.