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The U.S. houses what percentage of the world’s airports? If you asked several people this question and averaged their guesses, you would probably end up closer to the right answer (30.5 percent) than if you asked just one person. This “wisdom of the crowd” effect has long been recognized, but scientists have recently gone a step further by showing that the strategy works even when the “crowd” consists of only one person.
Psychologists Edward Vul of the Massachusetts Institute of Technology and Harold Pashler of the University of California, San Diego, asked 428 participants various trivia questions and then, without warning, asked them to guess again later. On average, a person’s combined responses were more accurate than either of his or her guesses alone, the authors reported in Psychological Science in July.
The findings support the notion that cognition may be described as statistical inference, meaning that people base their thoughts and judgments about the world on statistical probabilities, Vul says. When trying to answer a trivia question, people construct a range of possible values based on their knowledge. Each guess then represents one sample from that distribution, he says. For example, people might approach the question about the percentage of airports by imagining a world map showing the distribution of airports, Vul explains, “but because their knowledge is probabilistic the map they construct will be different for each guess.”
Note: This story was originally printed with the title, "Go Ahead, Change Your Mind".
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12 Comments
Add Commentthis is a totally wrong article.The editor should be shame of their ability of selecting topics
Reply | Report Abuse | Link to thiswhy?
Reply | Report Abuse | Link to thisPlease give evidence or articles that disprove this article
Reply | Report Abuse | Link to thisplease add up my QQ:840974448.I have smething inportant to tell you .thank you !
Reply | Report Abuse | Link to thisvery interesting...
Reply | Report Abuse | Link to thisvery interesting...
Reply | Report Abuse | Link to thisthis is called the central limit theorem. Its the basis for all statistical inference.
Reply | Report Abuse | Link to thisThis is called the central limit theorem - it is the basis for all statistical inference.
Reply | Report Abuse | Link to thisIf you don't know the answer to begin with, and answering with three guesses....what does that make you? I'd rather say I don't know when
Reply | Report Abuse | Link to thisI come across something I don't know the answer to.
so what!
Reply | Report Abuse | Link to thisThis article neglects to specifically remove those participants that actually knew the answer and answered correctly both times. If you know the answer then your chance of the average of both answers being more correct is 0%. The author should have provided more detail. I am also curious as to what the benefit of knowing this is supposed to be and what impact of such knowledge would have on people using guess averaging as opposed to the ignorance of the study participants. Would this cause differences in their guesses? Would the averages be more or less accurate or would it have no impact?
Reply | Report Abuse | Link to thisCentral limit theorem obviously applies, but you still run into the problem of a small sample size. It doesn't seem to logical that the average of only three guesses would yield a more accurate answer than any of the individual guesses alone. The reason large crowds tends to be more accurate is that you smooth out all the individual biases or heuristics (hence the wisdom of crowds). So would it really possible to get a similar smoothing effect if one person simply provides two additional guesses?
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