Disinformation techniques in charts

Charts are not a neutral window onto data: the conclusion a reader takes away depends not only on the data but also on the design of the chart, its context and the reader.

The lecture will present the most common techniques for distorting what a chart says, from a truncated or inverted y-axis and the aspect ratio to the choice of time period, misleading titles and colour scales. It will explain why these techniques work in terms of visual perception and why simply warning readers about them is not enough. Finally, it will present the results of the speaker’s own studies, in which seven of the nine techniques tested distorted readers’ judgement, and visualisation literacy played a bigger role than changes to the chart.