If you apply for a job and the company is interested, they will look at your social media presence to find risky behavior that they're not allowed to come right out and ask about.

A new paper, by people who are not actually in the business of hiring anyone, finds that companies may have a fundamental misunderstanding of online behavior and, as a result, may be eliminating desirable job candidates.

The psychologists tested 175 study participants to measure the personality traits that companies look for in job candidates, including conscientiousness, agreeableness and extraversion. The participants were then surveyed on their Facebook behavior, allowing researchers to see which Facebook behaviors were linked to specific personality traits.

"Companies often scan a job applicant's Facebook profile to see whether there is evidence of drug or alcohol use, believing that such behavior means the applicant is not 'conscientious,' or responsible and self-disciplined," says Dr. Lori Foster Thompson, a professor of psychology at NC State and co-author of a paper describing the study.

That there was no significant correlation between conscientiousness and an individual's willingness to post content on Facebook about alcohol or drug use. Of course, employers are not just looking for conscientiousness, in many cases, they are instead looking for people who will need rehab or might wreck a company car.

Still, the psychologists think that is what department managers are seeking in employees. "This means companies are eliminating some conscientious job applicants based on erroneous assumptions regarding what social media behavior tells us about the applicants," says Will Stoughton, a Ph.D. student at NC State and lead author of the paper.

And companies that are looking for extroverts – such as those hiring for sales or marketing positions – do even worse. Extroverts were significantly more likely to post about drugs or alcohol on Facebook, so companies weeding out those applicants are likely to significantly limit the pool of job candidates who are extroverts.

The psychologists did find one online indicator strongly correlated to the personality traits that employers look for. Study participants who rated high on both agreeableness and conscientiousness were also very unlikely to "badmouth" or insult other people on Facebook.

"If employers plan to keep using social media to screen job applicants, this study indicates they may want to focus on eliminating candidates who badmouth others – not necessarily those who post about drinking beer," Stoughton says.