群众的智慧：无事生非
Wisdom of crowds: much ado about nothing
摘要：
一个令人困惑的想法是，对一个量的大小的独立估计的组合导致一个非常准确的预测，这比任何一个或至少比大多数个人估计都要好，这就是所谓的群体智慧。在这里，我们使用费城联邦储备银行的专业预测数据库的调查，面对这一现象的统计和心理物理学解释。总的来说，我们发现数据不支持任何对群体智慧的解释。特别是，我们发现的方差（或多样性）的估计和人群误差之间的正相关性不同意的多样性预测定理的一些解释。此外，与心理物理学增广梅花形模型的预测相反，我们发现估计的偏斜没有提供关于人群误差的信息。更重要的是，我们发现群体在不到2%的预测中击败了所有个体，在不到70%的预测中击败了大多数个体，这意味着随机选择的个体有可能比群体表现得更好。这些结果与由无偏见的预测者组成的非自然群体的表现形成鲜明对比，这些预测者在几乎所有的预测中都击败了大多数人。现实世界中的群体相对于其成员的适度统计优势并不能证明关于其智慧的争论是合理的，这很可能是选择性注意力谬误的产物。
英文摘要：
The puzzling idea that the combination of independent estimates of the magnitude of a quantity results in a very accurate prediction, which is superior to any or, at least, to most of the individual estimates is known as the wisdom of crowds. Here we use the Federal Reserve Bank of Philadelphia's Survey of Professional Forecasters database to confront the statistical and psychophysical explanations of this phenomenon. Overall we find that the data do not support any of the proposed explanations of the wisdom of crowds. In particular, we find a positive correlation between the variance (or diversity) of the estimates and the crowd error in disagreement with some interpretations of the diversity prediction theorem. In addition, contra the predictions of the psychophysical augmented quincunx model, we find that the skew of the estimates offers no information about the crowd error. More importantly, we find that the crowd beats all individuals in less than 2% of the forecasts and beats most individuals in less than 70% of the forecasts, which means that there is a sporting chance that an individual selected at random will perform better than the crowd. These results contrast starkly with the performance of non-natural crowds composed of unbiased forecasters which beat most individuals in practically all forecasts. The moderate statistical advantage of a real-world crowd over its members does not justify the ado about its wisdom, which is most likely a product of the selective attention fallacy.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
