Sunday, January 02, 2011
The Wisdom of Diversity
At the Stock Fair, Mr. Galton watched as dozens of individuals paid a fee of sixpence to guess the weight of a large ox. Several people guessed reasonably close to the ox's correct weight. Later, however, Galton collected all of the guesses, adding them up and dividing the result by the total number of guesses. To his astonishment, the averaged answer from the crowd came to 1,197 pounds, off by only one pound from the correct answer of 1,198.
Thus, said Galton, "This result is, I think, more creditable to the trustworthiness of a democratic judgment than might have been expected." And thus was born The Wisdom of Crowds.
If you are not sure about the right answer to a quantifiable question, ask several people. Not one individual in Galton's experiment had guessed as close to the correct answer as was the averaged answer. Similarly, if you ask, say, fifty people to guess how many jelly beans are in a large jar, the averaged answer will often be closer than the closest individual answer.
A couple of caveats: in order for the wisdom of crowds to work, each participant has to be (a) informed about the subject, (b) able to control his or her own destiny, (c) highly independent and not influenced by others, and (d) open to new ideas and experiences. (See The Science of Liberty, by Timothy Ferris, pp. 29-34)
In studying the wisdom of crowds, another interesting tidbit was teased to the surface--the accuracy of crowd predictions grows better as the diversity (socially, sexually, ethnically, etc.) of the crowd increases.
Which makes me think it very likely that members of the Democratic Party in the Utah State Legislature, being more diverse than their Republican counterparts, make better overall decisions than do the Republicans. (See, for example, here.)
Which makes me also think that maybe God knew what he was doing after all when he did that Tower of Babel thing...