In 1906, British scientist and writer Sir Francis Galton visited a livestock fair where a competition was being held: Fairgoers were asked to guess the weight of a butchered ox. Although the 787 estimates given spanned a wide range of weights, the mean estimate was only one kilogram off the mark. This phenomenon, called the "wisdom of crowds", arises when individual judges do not all make the same errors. Provided that some estimates are too high and others are too low, the errors tend to cancel one another out.
The "wisdom of crowds" can also be conjured within a single person by averaging several non-redundant estimates from the same person*. Urging people to think differently when generating a new estimate can boost this averaging gain ("dialectical bootstrapping" **). In their ongoing work, the researchers are investigating further ways to use dialectical bootstrapping to boost the "inner crowd."
* Herzog, S. M., & Hertwig, R. (2014). Harnessing the wisdom of the inner crowd. Trends in Cognitive Sciences, 18, 504–506. doi:10.1016/j.tics.2014.06.009
** Herzog, S. M., & Hertwig, R. (2009). The wisdom of many in one mind: Improving individual judgments with dialectical bootstrapping. Psychological Science, 20, 231–237. doi:10.1111/j.1467-9280.2009.02271.