Every day we are bombarded with poorly designed graphics ranging from TV news reports to magazine info-graphics, horribly pedestrian Powerpoint and Excel charts to signage that is impossible to decipher. The main problem with these illustrations is there is too much to them: they include information we don’t need that distracts from the real story. It’s chart junk.
Edward Tufte coined term chart junk in his 1983 book The Visual Display of Quantitative Information. Chart Junk is the superfluous graphics that get added to a chart or graph which add no value, distracting viewers with information that isn’t vital to communicate. Chart junk happens when the design and flare of the chart becomes more important than the information the chart is meant to convey.
As you create charts and graphs, you are telling a story. You are imposing your bias and view as a designer onto the data. It is best if you can do it in an independent manner, to let the data shine through, but this isn’t always possible. Even people who have written books on the topic of chart design have fallen prey to chart junk. Nigel Holmes’ book entitled, Designer’s Guide to Creating Charts and Diagrams, makes me cringe just looking at the cover!
But there might be a new side to this story. A newly published paper entitled, “Useful Junk? The Effects of Visual Embellishment on Comprehension and Memorability of Charts" suggests that chart junk isn’t as bad as it seems. In fact, it can even be valuable in certain circumstances. If you are trying to maximize recall and general trends, then having kitschy chart junk tends to build better associations and help people remember at a later date.
One of the examples used in the report was a chart about the price of diamonds in the late 70s and early 80s. Rather than just using a regular line graph, the designer incorporated an image of a woman’s leg to accentuate the line. In the wrong hands this sort of graphic is often wasteful and distracting. But when test participants were asked about the charts several weeks later, they could remember the contents of the info-graphic better when the additional image was present. The had associated the data with the graphic.
These results suggest that extraneous information isn’t always bad. You don’t always have to show data and only data when presenting. In certain circumstances pictures can aid with memory and recall (though not necessarily understanding).
In other cases, such as when you are displaying exact values for cross-comparison, then minimizing ink and removing chart junk is paramount.
You always need to remember that your goals, your readers’ goals and the data may not always align and you need to choose the right tool for the job. And chart junk, in some cases, might just be a valuable tool.