Being bald, as opposed to having thin hair, is perceived to be more masculine thanks to Hollywood alpha males like Bruce Willis.

Hubert Boesl/dpa/Corbis

hile having no hair may seem to offer few advantages, a new study from The Wharton School at the University of Pennsylvania begs to differ. Researchers found that men with shaved heads are perceived to be more masculine and dominant — not to mention "on average one inch taller, and able to bench press 15 more pounds than other men," says Eric McClaughlin at ABC News. Meanwhile men whose hair is thinning but not shaved off — those stuck in comb-over purgatory — were viewed as weak. How did Wharton come to these conclusions? Researchers conducted three experiments, says Rachel Emma Silverman at The Wall Street Journal:

In one of the experiments, [they] showed 344 subjects photos of the same men in two versions: one showing the man with hair and the other showing him with his hair digitally removed, so his head appears shaved.

...the subjects reported finding the men with shaved heads as more dominant than their hirsute counterparts. In one test, men with shorn heads were even perceived as an inch taller and about 13 percent stronger than those with fuller manes...

The study found that men with thinning hair were viewed as the least attractive and powerful of the bunch, a finding that tracks with other studies showing that people perceive men with typical male-pattern baldness — which affects roughly 35 million Americans — as older and less attractive. For those men, the solution could be as cheap and simple as a shave.

Why are men with shaved heads perceived to be more masculine?
Analysts say the look is associated with alpha males, such as members of the military, bald action stars like Bruce Willis and Vin Diesel, and athletes like Michael Jordan. Thinning hair, on the other hand, is more closely associated with sad sacks like the Seinfeld character George Costanza.   

So how does this play out in the corporate world?
The study suggests that power-buzzed men are seen as being better leaders, which may explain why Amazon's Jeff Bezos and Microsoft's Steve Ballmer have gone for the egghead look. At the very least, it's better than the comb-over alternative. 

And how about men with a full head of hair?
Sorry, they're still seen as more attractive, if less dominant, than their hairless counterparts, according to the study.