Hulton Archive via Getty Images, file

4th July 1776: The signatures on the Declaration of Independence, a document in which American colonists proclaimed their political separation from British rule. (Photo by Hulton Archive/Getty Images)

John Hancock must have been an egomaniac. Large signatures are common among narcissists, finds new research from the University of North Carolina's Kenan-Flagler Business School and the University of Maryland. The study examined the signatures of more than 600 CEOs and found that the most outsized signers were among the highest paid, but were also more likely to run their companies into the ground. Those factors indicate an inflated sense of self, a disregard for people's input, and other narcissistic tendencies, explains study author Nicholas Seybert, Ph.D., an assistant professor at the University of Maryland. (Okay, it isn't a man's world anymore. Narcissism notwithstanding, are there any advantages to being guy?)

Past research shows large signatures reveal high self-esteem and social dominance among the general public. Why? People see a signature as a stand-in for themselves, and a bigger, more prominent moniker reveals a person's larger-than-average self-regard, the research explains. If you have a big autograph, you're not necessarily a narcissist--though you probably are an alpha male, Seybert says. But when applied to CEOs--a group already likely to favor people with inflated egos--big signatures are also likely to reveal narcissistic traits. (Avoid the 5 ways to ruin a first impression, and ace that crucial first date.)

Here are more strange clues into your personality.

If you love boiled eggs, you're more likely to be messy.
Boiled egg lovers are more disorganized and more likely to get divorced, shows a study of 1,100 people funded by the British Egg Industry Council and published by Mindlab International. Fried egg fans have the highest sex drive, the study finds. Poached-egg eaters are outgoing and happy, scrambled aficionados are guarded, and omelet lovers are self-disciplined, the study says.

If you drive a red car, you're more reckless.
People who drive red cars are more aggressive and reckless, shows a study from CW Marketing Research. The Oregon-based firm also found people with green cars have the most positive outlook on life, dark blue or silver-car owners are upbeat, and black car owners lack self-confidence. Why? A growing body of research shows certain visual cues--such as colors--are tied to emotional and behavioral cues in your brain. These cues can influence the colors you find appealing depending on your personality type, according to a University of Cambridge study. (And while you're in the car, make sure to eat smart. Grab a copy of Eat This, Not That! 2013 for your next road trip.)

If you have too many Post-it Notes, you're probably overwhelmed.
An empty or unpersonalized desk indicates a lack of dedication or job dissatisfaction, according to a University of Texas study. Excessive Post-it Notes mean you're overwhelmed, while a plant proves you have no plans to leave your gig, the UT study shows. The researchers say people see their personal space as extensions of themselves, and so how they arrange or design those spaces provide clues to their personalities. People who have candy bowls or lots of office supplies are more likely to be outgoing and social, and motivational items often reveal a worker who pushes himself, the study adds.

If you love Metallica, you're more likely to be lazy.
Classical, jazz, and heavy metal music lovers are all generally creative and at ease, but metal-heads are more likely to also be lazy and introverted, finds a study of 36,000 people from Scottish researchers. Blues fans tend to have high self-esteem, rap fans are pretty outgoing, and country lovers are generally hardworking, the study shows. Indie rock snobs tend to be harsh and lack self-esteem, the study found. (Discover the 6 crazy ways music improves your life.)

More from Men's Health: 
What Your Tweets Say About You
Find the Perfect Scent for Your Personality
What Your Drink Says About You

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Narcissists are well aware of their me-first tendencies and may not be completely clueless of how their personalities and reputations come across to others, a new study claims. This finding challenges the belief that people with super-sized egos -- and even bigger heads -- lack self-insight. 

In a study cleverly titled "You Probably Think This Paper's About You" in the July issue of the Journal of Personality and Social Psychology, researchers were surprised to find that narcissists did, in fact, see themselves as narcissistic and realized that other people view them less positively as they see themselves.

A narcissist is someone who is arrogant and condescending, enjoys bragging and arguing, and often tries to be the center of attention, says Erika Carlson, a graduate student in psychology at Washington University in St. Louis, and the study's lead author.

Carlson and her research team wanted to determine to what extent the perceptions of people who are full of themselves varies based on how they view themselves, how they are seen by others, and how they believe others see them.

One experiment looked at 110 college students (41 men, 69 women) who worked in small groups once a week throughout a semester. During the first and last week they met, each group rated its members on 10 personality traits and classmates also completed self-evaluation forms.

As expected, folks who think they're special scored themselves higher on positive characteristics, such as intelligence, likability, and physical attractiveness. Even though they made good first impressions with their peers, those lofty views soured over time but narcissists realized that their reputations had taken a hit.

"If you told narcissists that they are 'narcissistic' and that others don't see them as positively as they see themselves, they would not be surprised," points out Carlson. And while college is an age when young people appear more self-absorbed, Carlson speculates that even if her research participants included middle-age and older narcissists, the results might be similar if not more extreme.

She suspects that although narcissists would receive feedback about their behavior, they probably think others don't see their brilliance because they're jealous or not smart enough to recognize it.

A second experiment involved 274 Air Force recruits (154 men, 120 women) who had spent six weeks together in basic training. Unlike the previous study, the recruits knew each other better than mere acquaintances, and scientists used a clinical tool to measure narcissism instead of self-reported information.

Researchers found once again that people who were the most self-centered viewed themselves that way and believed their coworkers would perceive them as big-headed, too.

"Narcissists know that others do not share their positive self-views," says Carlson. But her hunch is these self-absorbed individuals view their narcissism as a character strength that brings them personal gain and helps them get ahead.

When asked how best to handle the narcissists in our lives, Carlson suggests, "My guess is the trick is to use their desire for respect and status as a carrot to evoke positive changes." 

We bet you think these links are about you:

• Pop songs reflect our 'me me me' attitudes
• Study: Creative, Don Draper-types are full of themselves

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