Surprisingly popular
The surprisingly popular answer is a wisdom of the crowd technique that taps into the expert minority opinion within a crowd.[1] For a given question, a group is asked both "What do you think the right answer is?" and "What do you think the popular answer will be?" The answer that maximizes the average difference between the "right" answer and the "popular" answer is the "surprisingly popular" answer.[2]
Example
Question to be determined:
Is Philadelphia the capital of Pennsylvania?
Questions asked to the group and the response rates:
Is Philadelphia the capital of Pennsylvania?
- Yes: 65%
- No: 35%
What do you think most people will respond to that question?
- Yes: 75%
- No: 25%
The difference between the answers to the right question and the popular question:
- Yes: 65% − 75% = −10%
- No: 35% − 25% = 10%
Thus, the No answer is surprisingly popular (10% > −10%). Because of the relatively high margin of 10%, there can be high confidence that the correct answer is No. (The capital is indeed not Philadelphia, but Harrisburg.)
An illustrative breakdown of this follows. There are four groups of people.
- A - "Philadelphia is the capital, and others will agree." (This group answers yes/yes.)
- B - "Philadelphia is the capital, but most others won't know that". (This group answers yes/no.)
- C - "Harrisburg is the capital, and others will agree." (This group answers no/no.)
- D - "Harrisburg is the capital, but most others won't know that." (This group answers no/yes.)
This technique causes groups A and C to be eliminated from consideration and measures the difference in size between groups B and D.
Both groups B and D think they know something other people don't, but B is wrong and D is right. In cases where people feel like they have "inside" knowledge, it's more often the case that it's because they are correct and knowledgeable (group D), not because they are misled (group B).
See also
- Keynesian beauty contest
- Guess 2/3 of the average
- Focal point (game theory), also known as Schelling point
References
- Akst, Daniel (February 16, 2017). "The Wisdom of Even Wiser Crowds". The Wall Street Journal. Retrieved 16 May 2018.
- Dizikes, Peter (January 25, 2017). "Better wisdom from crowds". MIT News. Retrieved 16 May 2018.
Further reading
Prelec, Dražen; Seung, H. Sebastian; McCoy, John (25 January 2017). "A solution to the single-question crowd wisdom problem". Nature. 541: 532–535. doi:10.1038/nature21054. PMID 28128245.