Lesson 130 · 2 min
Misleading charts
A chart can use real numbers and still mislead you through its scale, its time range or what it leaves out.
The most common trick is a cut axis. If the bars start at 95 instead of 0, a change from 96 to 98 looks like a huge jump.
Other tricks: choosing only the months that fit the story, comparing totals when per-person numbers matter, or using a 3D pie chart that makes one slice look bigger.
AI makes charts in seconds, and it will happily draw whatever the person asks for. A smart-looking chart in a post is no sign that anyone checked it.
Read the axis labels, the units and the dates first. Ask what the chart would look like with the full range, and where the numbers came from.
Do it now
Redraw one chart
- 1. Find a chart in the news or a social post.
- 2. Check where the vertical axis starts and what time range is shown.
- 3. Sketch the same numbers with the axis starting at zero and see if the story changes.
Quick check
Words from this lesson
- AI literacy
- Knowing enough about how AI works to use it well, spot its mistakes and decide when not to use it.
- Automation bias
- Our habit of trusting a machine's answer too readily, even when our own judgement or other evidence says otherwise.