Visualizing the Wisdom of the Inner Crowd
Written with Leonard J. Chen
Posted Dec 13, 2012
In a provocative paper, Herzog & Hertwig (HH, 2009) showed that the aggregation effect (vox populi, wisdom of the crowd) can be observed within individuals. HH asked respondents to provide a second round of estimates after carefully contemplating how and why the first estimates could have been wrong. They then averaged the two estimates for each individual and re-assessed accuracy.
HH noted that the average estimate will be better than the first estimate, E1, if the second estimate, E2, falls within the gain range. If, for example, E1 is below the true value, T, E1 is the lower bound of the gain range and E1 + 4(T-E1) is the upper bound. If, for example, the question is when Harvard University was founded (T = 1636) and E1 = 1620, then the inner crowd will be wise unless E2 > 1683 or < 1621. Analogously, if E1 is greater than T, E1 is the upper bound of the gain range.
We applied Herzog and Hertwig’s method to an area of social judgment. Respondents (N = 127) read 10 personality statements (e.g., “My hardest battles are with myself.”) and made two consensus estimates (What percentage of people agree with the statement?).
Though small in size, the effects of the internal crowd make an important psychological point. Individuals can improve their perceptions, memories, and predictions by generating diverse judgments and averaging them. The strategy recommends itself in betting contexts, when money is at stake. A farmer who engaged in dialectical bootstrapping could have outperformed most of his competitors. Aside from the improbability that people might think of this strategy on their own, it remains to be seen how they respond to it when asked to use it. Some may argue that they would rather choose between E1 and E2 than average.
We thank Stefan Herzog and Ralph Hertwig for sharing their data with us.
Fiedler, K., & Krueger, J. I. (2012). More than an artifact: Regression as a theoretical construct. In J. I. Krueger (Ed.). Social judgment and decision-making (pp. 171-189). New York, NY: Psychology Press.
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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.x
White, C. M., & Antonakis, J. (2013). Quantifying accuracy improvement in sets of pooled judgments: Does dialectical bootstrapping work? Psychological Science.