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News Release

October 22, 2008


Adam Gorlick, News Service: (650) 725-0224,

Let's face it: Researchers say voters swayed by candidates who share their looks

Made up your mind who to vote for?

Maybe it's because you like the looks of the candidate. Or maybe it's because the candidate looks a little like you, even if you don't realize it.

In a paper slated to be published in the December issue of Public Opinion Quarterly, Jeremy Bailenson, an assistant professor of communication, and Shanto Iyengar, the Harry and Norman Chandler Professor in Communication, say that people are subconsciously swayed by candidates who share their facial features.

"The field of political science has been dominated by the main ideal that voters are rational and that voters base their decisions on substance and issues and policy," Bailenson said. "We wanted to say, 'Well, how much of our decisions are actually based on superficial qualities?'"

The answer: More than they expected.

In three experiments, the researchers and their graduate students worked with cheap, easy-to-use computer software to morph pictures of about 600 test subjects with photos of politicians. And they kept coming up with the same results: For the would-be voters who weren't very familiar with the candidates or in perfect lockstep with their positions or political parties, the facial similarity was enough to clinch their votes.

Social scientists have long known that people are more inclined to be friendly and helpful to those who obviously look like them. But what surprised Bailenson and Iyengar was that nobody swayed by one of the morphed photos could tell they were looking at a blended image.

"The big finding No. 1 is that when we do this, no one has any conscious, explicit idea that it's going on," Bailenson said. "The second big finding is that despite the fact they don't consciously detect these processes, it affects their behavior. When the candidate looks more like you, you are more likely to vote for that candidate."

The first experiment was conducted about a week before the 2004 presidential election with a group of 240 potential voters. The test subjects, who had no idea what the experiment was about, were split into three groups and shown pictures of incumbent President George Bush and his challenger, Sen. John Kerry.

One group was shown untainted pictures of both candidates. A second group had their photos morphed with a picture of Bush. And the third group had their photos spliced with a picture of Kerry. The doctored photos blended 40 percent of the test subjects' facial features with 60 percent of the candidates' natural looks—a ratio the researchers decided could change a photo enough without anyone consciously noticing.

Those who looked at the real photos said they would vote for Bush over Kerry by 46 to 44 percent, predicting the same two-point spread that marked Bush's victory in the actual election.

When the other groups examined the morphed photos, the gap grew markedly.

Those who had their photos combined with Bush gave the Republican a 13-point victory, while those blended with Kerry gave the Democrat a 7-point advantage.

"The outcome of this election among our sample was decided not on the issues or the character of John Kerry or George Bush, but based on how similar the image of Bush or Kerry was to the voter," Bailenson said. "It was a huge surprise for us."

Their other experiments made similar points by judging people's reactions to lesser-known candidates in this year's presidential primary race and the 2006 Florida gubernatorial election. When test subjects' images were mixed with the candidates, they were more inclined to vote for them.

"When you look at who's really swapping their votes, it's the independent voters and weak party affiliates," Bailenson said. "It's the moderate people. If your heart and mind are set on voting for George Bush, this is not going to change your mind."

Bailenson said he is unaware of any campaign using the technology to manipulate voters, and said follow-up tests showed that people reacted negatively when they knew their picture was being melded with a candidate's.

But with free and public sources of mug shots easily found on photo-sharing websites and in motor vehicle department databases, it's easy to imagine a candidate targeting a potential voter with an ad featuring a morphed photo.

"From an ethical standpoint, I'd hope we never see that happen," Bailenson said, adding that it takes about 15 minutes and $20 to make a morphed photo with a computer. "Candidates spend seven-, eight- or nine-figure budgets on their campaign. So it's not outrageous to think that in a swing state such as Ohio or Pennsylvania, you can have 2,000 people sitting in a room morphing every single citizen in the state. That's a job that's going to take three weeks and not three years."



Jeremy Bailenson, Communication: (650) 723-0701,

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