
Additional factors include the level of light in the pub or club, the drinker's own eyesight and the
KEY TO FORMULA

S = smokiness of the room (graded from 0-10, where 0 clear air; 10 extremely smoky)
L = luminance of 'person of interest' (candelas per square metre; typically 1 pitch black; 150 as seen in normal room lighting)
Vo = Snellen visual acuity (6/6 normal; 6/12 just meets driving standard)
d = distance from 'person of interest' (metres; 0.5 to 3 metres)
They all add up to make the aesthetically-challenged more attractive, according to the formula
. The formula can work out a final score, ranging from less than one - where there is no beer goggle effect - to more than 100.
Nathan Efron, Professor of Clinical Optometry at the University of Manchester, said: "The beer goggles effect isn't solely dependent on how much alcohol a person consumes, there are other influencing factors at play too.
The research was commissioned by eyecare firm Bausch & Lomb PureVision.
A poll showed that 68% of people had regretted giving their phone number to someone to whom they later realised they were not attracted.
A formula rating of less than one means no effect. Between one and 50 the person you would normally find unattractive appears less "visually offensive".

Non-appealing people become suddenly attractive between 51 and 100. At more than 100, someone not considered attractive looks like a super model.