This is scientific American 60 second science. I'm Christopher Intagiyata.

You ever order a drink and feel stiffed on the poor?

Well, before you bother your bartender, take a closer look at the size of your glass.

So people will generally perceive there to be less in larger containers than smaller ones.

Theresa Martow, a behavioral scientist at the University of Cambridge in England.

She and her colleagues had analysed how larger portions and larger plates lure us into eating more food.

And they wondered, could the same be true for

alcohol.

So the researchers convinced the staff at a local bar to run an experiment.

Every two weeks for four months they'd rotate the bar's wine glasses from the

standard 300 milliliter size to either slightly larger 370 millilters or

slightly smaller 250 millililaters.

And see how the size of the glass affected Patron's drinking habits,

even though the poor, the volume of alcoholic beverage,

was unchanged.

Turns out, serving wine in smaller glasses had no measurable effect,

but the large glasses, they boosted wine sales 10%.

Even after controlling for day of the week, temperature, holidays, and so on.

The reason, she says,

When the wine, the same volume is being served in the larger glass,

that people are probably perceiving that they've got less in the larger glass, that people are probably perceiving that they've got less in there.

Which she says means they might drink more.

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