People think they are better looking than they really are (Kalexanderson/Flickr)

People think they are more attractive and generous than they actually are, researchers have found.

Writing for the Scientific American, Ozgun Atasoy, a doctoral candidate in the Department of Marketing at Boston University, who focuses on the effects of deception on the deceiver and the deceived, looked at a recent Dove advertising campaign.

He noted that the Dove Real Beauty Sketches campaign showed women describing their appearance to a sketch artist who cannot see them. Their appearance is also described to the artist by a stranger who has just met them. The artist then produces two images.

"Much to their amazement and delight, the women realise that the drawings based on strangers' descriptions depict much more beautiful women. The video ends: 'You are more beautiful than you think'," Atasoy wrote.

"However, what Dove is suggesting is not actually true. The evidence from psychological research suggests instead that we tend to think of our appearance in ways that are more flattering than are warranted."

He looked at research by Nicholas Epley of the University of Chicago and Erin Whitchurch of the University of Virginia, who studied how people perceive their own appearance.

The researchers took pictures of study participants and then made two modified versions - one where they were made more attractive and another where they were less attractive.

Participants were then asked to pick out the original, unmodified photo. Findings showed people tended to pick the picture that had been made more attractive. They also found that when the same task was done with a stranger, whom the participant had met a few weeks earlier, they picked the unmodified version.

Da Vinci's Narcissus, who fell in love with his own reflection (wiki commons)

Atasoy said self-enhancement meant that people overestimated their positive behavioural traits: "For example, people overestimate the amount of money they would donate to charity while accurately predicting others' donations."

He continued: "Most people believe that they are above average, a statistical impossibility. For example, 93% of drivers rate themselves as better than the median driver. Of college professors, 94% say that they do above-average work.

"If you think that self-enhancement biases exist in other people and they do not apply to you, you are not alone. Most people state that they are more likely than others to provide accurate self-assessments."

Explaining why people have a rose-tinted view of themselves, Atasoy said self-enhancement is socially desirable because it allows people to 'lie' without actually deceiving anyone.

"People may try to deceive others about their characteristics, but deception has two main disadvantages," he said.

"First, it is cognitively taxing because the deceiver has to hold two conflicting representations of reality in mind - the true state of affairs and the deception. The resulting cognitive load reduces performance in other cognitive functions.

"Second, people are good at detecting deception and they show strong negative emotional reactions toward deceivers. Since in self-enhancement people truly believe that they have desirable characteristics, they can promote themselves without having to lie. Self-enhancement also boosts confidence.

"Dove's premise is wrong. But thinking we are more beautiful than we really are may not be such a bad thing."