Psychology 心理学
The crowd within 三智五猜
Jun 26th 2008
From The Economist print edition
A battle of ideas is going on inside your mind
多猜出真知
THAT problem solving becomes easier when more minds are put to the task is no more than common sense. But the phenomenon goes further than that. Ask two people to answer a question like “how many windows are there on a London double-decker bus” and average their answers. Their combined guesses will usually be more accurate than if just one person had been asked. Ask a crowd, rather than a pair, and the average is often very close to the truth. The phenomenon was called “the wisdom of crowds” by James Surowiecki, a columnist for the New Yorker who wrote a book about it. Now a pair of psychologists have found an intriguing corollary. They have discovered that two guesses made by the same person at different times are also better than one.
一般说来人多好办事，然而有现象表明人多远不只是好办事。要求两个人回答象这样一个问题“伦敦双层巴士有多少个窗户？”，然后平均他们俩的答案，你会发现他们俩的平均值要比单个人回答的更准确。如果多问一群人，而不是一对，其平均值常常更接近真实答案。New Yorker 的专栏作家 James Surowiecki 把这一现象称为“集体的智慧”，他写过一本书探讨这个问题。现在有两位心理学家发现一个引人兴趣的推论，那就是同一个人在不同时间对一个问题做出两次猜测回答也比一次猜测的答案更准确。
That is strange. Until now, psychologists have assumed that when people make a guess, they make the most accurate guess that they can. Ask them to make a second and it should, by definition, be less accurate. If that were true, averaging the first and second guesses should decrease the accuracy. Yet Edward Vul at the Massachusetts Institute of Technology and Harold Pashler at the University of California, San Diego, have revealed in a study just published in Psychological Science that the average of first and second guesses is indeed better than either guess on its own.
奇怪的是，直到现在，心理学家还是认为当人们回答问题时，他们会尽其所能做出最正确的猜测，让他们做第二次猜测，其结果肯定更不准确。如果真是这样的话，那么两次猜测的平均值应该会降低准确度。然而麻省理工大学的Edward Vul 和圣地亚哥州芝加哥大学的Harold Pashler 刚刚发表在心理科学杂志的研究揭示实际上两次猜测的平均值比其前后两次的任一次猜测的答案更准确。
The two researchers asked 428 people eight questions drawn from the “CIA World Factbook”: for example, “What percentage of the world’s airports are in the USA?” Half the participants were unexpectedly asked to make a second, different guess immediately after they completed the initial questionnaire. The other half were asked to make a second guess three weeks later.
这两位研究员从“美国中央情报局世界各国概况”一书中选出8个问题，并要求428个人回答这些问题：譬如，“世界上有百分多少机场在美国？” 完成初次问卷调查后，一半参与者出乎意料地被要求立即对问题的答案做出第二次不同的猜测，另一半人则在三周后做第二次的猜测。
Dr Vul and Dr Pashler found that in both circumstances the average of the two guesses was better than either guess on its own. They also noticed that the interval between the first and second guesses determined how accurate that average was. Second guesses made immediately improved accuracy by an average of 6.5%; those made after three weeks improved the accuracy by 16%.
Vul博士和Pashler博士研究发现上述两种情景下两次猜测的答案的平均值比各自的前后两次的任一次猜测更准确。他们也注意到两次回答的时间间隔决定了其平均值的准确程度。立即做第二次猜测的参与者其两次的平均值的准确度提高6.5%，而三周后再做第二次猜测的则提高16%。
Even after three weeks, the result is still only one-third as good as the wisdom of several different people. But that this happens at all raises questions about “individuality” within an individual. If guesses can shift almost at random, where are they coming from?
即便是三周后的再次回答，其猜测的答案的准确度仍然只有达到几个不同人集体智慧结晶的三分之一。然而这种情况出现在单个人对所提的问题的不同时期的回答，也就是说，即便是三周后的再回答，其猜测的答案的准确度仍然只有达到同一人几个不同时期猜测的平均值的三分之一。如果不同猜测的变化是随机的，那么这些猜测的根据又是什么呢？
One answer could be that they are evidence for the “generate and test” model of creative thinking. This suggests that the brain is constantly creating hypotheses about the world and checking them against reality. Those that pass muster are adopted. Guessing the answers to questions you do not know the correct answer to, but have some idea of what the right answer ought to look like, could tap into such a system. A hive mind buzzing with ideas, as it were, but inside a single skull.
一种答案可能是，这些猜测是根据创造性思想的“生成检验法”模型。这表明人的大脑经常建立对周围世界的假设，接着根据实际情况检验他们假设的正确性。人们采纳了通过检验的假设。猜测你不知道的问题的答案时，正确的答案应该看起来象什么样子？你对此有些想法，并能用创造性思想的“生成检验法”模型进行检验。可以说，“三智五猜”尽在脑海中。
Translator : Reeve
Email: reeve.lin@yahoo.com
June 30, 2008
