Graphic Proof That Graphs Have Magical Powers of Persuasion

There’s nothing quite like a graph to make a claim seem a little more science-y. Show people a simple bar chart and they’re more likely to believe in a product’s scientific claims — even when the chart doesn’t add any new information, according to a paper in the journal Public Understanding of Science by Brian Wansink of the Cornell University Food and Brand Lab.

Here’s a look at the methodology of one of the studies described in the paper, according to the press release:

Half of the participants read a paragraph about the medication and the other half read the same paragraph with an accompanying graph. The graph did not provide any new information. Afterwards participants were asked: “Does the medication really reduce illness?”

Ah, said the participants who saw the graph. Look at all this Science. More from the press release:

Graphs helped convince almost all of the participants that the medication worked: 96.6% of those who saw the graph believed that the medication would effectively reduce illness, whereas only 67.7% of those who saw only the text believed that that it would reduce illness.

The authors conclude that advertisements that feature some kind of chart give the product a “scientific halo,” making the information read as a lot more believable —  even when the accompanying visual doesn’t actually add all that much.

But there is another, slightly less cynical way to read these findings, too. These charts didn’t present any false or exaggerated information; they just presented the facts —  in this case, that this medication reduced illness by 20 percent — in a visual way. So it could also be true that the bar charts helped people get a better handle on the information provided. Then again, not all commercials will be as honest as these earnest researchers from Cornell, so the graphs you see in ads may be misleading.

Either way, though, the authors’ main point holds: Take a close look at the claims being made in advertisements for new medications, foods, or other products, and don’t let yourself become blinded with science. Or “science,” as the case may be.

And if you don’t believe me that graphs make arguments more convincing, here is ironclad proof:

Graphs Have Magical Powers of Persuasion