Over 400,000 people visited Farnam Street last month to learn howto make better decisions, create new ideas, and avoid stupid errors. With more than 100,000 subscribers to our popular weekly digest, we've become an online intellectual hub. To learn more about we what do, start here.
If you’re having a party, what’s the best way to encourage safe driving?
In an amusing experiment, Brian Wansink and Koert van Ittersum, of Cornell and Georgia Tech, asked student volunteers and professional bartenders to pour out a shot (1.5 ounces) of a simulated liquor. They were instructed to pour carefully, to dispense as close to the exact 1.5 ounces as they could manage. Two types of glasses were used in the experiment: a tall, narrow highball glass and a short, squat tumbler (photo, below). Despite the different shapes, each glass had the same capacity. On average, the students poured 30 percent more “liquor” in the short tumblers than in the tall glasses. The professional mixologists were only a bit more accurate: They poured 21 percent more in the tumblers.
One conclusion: If you’re having a party and want to encourage safe driving — or just save on liquor — use tall, narrow glasses. Your guests, or the bartender, will pour less and think it’s more.
This result is relevant to the psychology of price, contends marketing consultant Rags Srinivasan.