Have you ever entered a jelly bean contest, where you try to guess the number of jelly beans in a jar? An interesting thing happens when you take the average of all the guesses.

Jack Traynor did exactly that. He brought a jar of beans (not the jelly kind) into two classes and asked the students to guess the number of beans inside. So the students crowded around the jar. They tried to count the beans or estimate the beans per volume or other such things to come up with their best guess. Then they wrote down their guesses and turned them in.

Traynor found that in both classes the average of the guesses came very close to the actual number of beans. But what really stood out was that the average of the guesses beat all but one or two guesses. In other words, only one or two students actually did better than the average of the whole group.

This effect is known as the wisdom of crowds, but it requires a key ingredient: Continue Reading…