We all know what pie charts, histograms, donut charts etc are. However, among the many that you come across, which ones are you likely to remember?
In an interesting study by Bateman et al., what they called “Useful Junk? The Effects of Visual Embellishment on Comprehension and Memorability of Charts”, they explored whether participants were more likely to remember graphs and charts if they were presented with chart junk.
Chart junk is a term coined by famous data visualiser, Edward Tufte who claimed that anything which does not play a role in telling the data should be removed from the chart. However in this study, they found that participants were more likely to recall details from the chart if they had “chart junk” elements in it.
Take a look at their abstract:
Guidelines for designing information charts often state that the presentation should reduce ‘chart junk’ – visual embellishments that are not essential to understanding the data. In contrast, some popular chart designers wrap the presented data in detailed and elaborate imagery, raising the questions of whether this imagery is really as detrimental to understanding as has been proposed, and whether the visual embellishment may have other benefits. To investigate these issues, we conducted an experiment that compared embellished charts with plain ones, and measured both interpretation accuracy and long-term recall. We found that people’s accuracy in describing the embellished charts was no worse than for plain charts, and that their recall after a two-to-three-week gap was significantly better. Although we are cautious about recommending that all charts be produced in this style, our results question some of the premises of the minimalist approach to chart design.
Conclusion:
Use embellishments or decorations appropriately, while ensuring that the data is readable without distracting the main attention from the data/story that has been told. This will go a long way in your reader’s memory.
Some examples of chart junk:


