We like to think we judge people's competence objectively, by carefully weighing their past actions and skills. But science shows a host of other factors, from height, to confidence, to even the way someone walks or smells can have unconscious effects on how we rate people's warmth, trustworthiness, and ability to do their job. 

Now, new research out of Princeton is adding yet another item to the long list of weird biases you need to look out for when you're hiring or job hunting. Even incredibly subtle differences in your clothing can affect how people judge your competence, the series of studies found, and these impressions form in under a second. 

Your clothes matter a shocking amount.

A suit, you might think, is just a suit. As long as someone shows up to a job interview neatly turned out in role appropriate attire, then the finer details of the suit (or hoodie) wouldn't matter. But when the Princeton team placed identical faces atop very slightly different outfits, they found people rated their perceived competence much differently. 

Specifically, when the clothes in question appeared subtly more expensive, whether the article of clothing in question was a suit or a T-shirt, people's perception of the wearer's confidence shot up. 

This was true even if the researchers explicitly instructed subjects to ignore clothing, when they told them that people in slightly more downmarket outfits actually out-earned their fancier clothed peers, and even if study subjects only viewed the pictures for 130 milliseconds, which is barely long enough to realize you're looking at a face. 

Is that depressing and unfair? Why, yes it is. And it's likely to be particularly demoralizing for those without a lot of money to spend on an interview outfit. It's an annoying reality the researchers readily acknowledged.

"Poverty is a place rife with challenges. Instead of respect for the struggle, people living in poverty face a persistent disregard and disrespect by the rest of society," commented study co-author Eldar Shafir. "We found that such disrespect -- clearly unfounded, since in these studies the identical face was seen as less competent when it appeared with poorer clothing -- can have its beginnings in the first tenth of a second of an encounter." 

The only upside here 

For job seekers out in the harsh real world, these results suggest it's probably worth springing for the fanciest interview outfit you can realistically afford (even for more casual workplaces). The larger initial outlay will actually make a difference, this new science strongly suggests. 

But there is also a message here for hiring managers, according to the authors, and it's the same old song about bias: at least if you know about it you can try to correct for it. "Knowing about a bias is often a good first step," Shafir says. 

Those truly committed toc compensating for humans' buggy brains might want to take more radical action. "A potential, even if highly insufficient, interim solution may be to avoid exposure whenever possible. Just like teachers sometimes grade blindly so as to avoid favoring some students, interviewers and employers may want to take what measures they can, when they can, to evaluate people, say, on paper so as to circumvent indefensible yet hard to avoid competency judgments," he suggests. (Tech tools exist to help with this but they're controversial.) 

While many employers might balk at the idea of hiring blind, Shafir notes that in academia (and orchestras) experiments with hiring without seeing candidates have actually yielded better results. But even if hiring just a voice and resume is too much for you, this research indicates any efforts you can make to reduce your exposure to candidates' clothing is likely to lead to more rational hiring.