The Jelly Bean Experiment

In part I of chapter one, Surowiecki talks about Jack Treynor's Jelly Bean Experiment:

A classic demonstration of group intelligence is the jelly-beans-in-the-jar experiment, in which invariably the group’s estimate is superior to the vast majority of the individual guesses. When finance professor Jack Treynor ran the experiment in his class with a jar that held 850 beans, the group estimate was 871. Only one of the fifty-six people in the class made a better guess.

Here is a short video demonstrating the experiment.


Another successful experiment.