The Crowd Isn’t So Wise After All
In modern society, we often rely on the “wisdom of the crowd,” which is the idea that decisions made by large groups of people are as good or better than decisions made by individuals. Our justice system relies on the wisdom of the crowd through trial by jury, and our government depends on the wisdom of the crowd by making democratic decisions. Unfortunately, the crowd isn’t always very wise.
Research from Arizona State University and Uppsala University in Sweden has found that a crowd can do as well or better than an individual when it comes to making a difficult or not clear cut decision, but can be worse than individuals when it comes to making decisions between two options where one is substantially better than the other. Researchers observed the behavior of ants who had to choose between two pieces of wood as a new dwelling. Even when one piece of wood was vastly superior to another, if more ants happened to find the inferior piece of wood first, some ants would mistakenly assume that they were at the better piece of wood. Those ants would in turn tell other ants that the inferior piece of wood was better, and eventually the whole colony would mistakenly believe the inferior piece of wood was the better of the two options, since the “voices” of the few ants who knew the true better piece of wood would be drowned out by the voices of the many. When ants made the same decision about the two pieces of wood individually, they had an almost certain chance of making the right decision, because there were no other ants to mislead them.
The phenomena of a group performing worse than an individual occurs in humans as well. When people make decisions based on what a group has done rather than their own information, the group as a whole can end up making incorrect decisions. The main reason groups are susceptible to performing so poorly is related to information cascades. Once a few people have made a decision based on their own information, subsequent people will make their decisions based on the past decisions of the group, disregarding their personal information. This can be seen in the red and blue marble experiment, where it is logically sound to disregard one’s information in favor of following the information of the group. The experiment demonstrates that the cumulative knowledge of a group can be very little, even though the group is large.
http://www.theatlantic.com/health/archive/2013/07/the-stupidity-of-the-crowd/278188/