Is the true 'wisdom of the crowd' to copy successful individuals?

Diversity of expertise at an individual level can increase intelligence at a collective level-a type of swarm intelligence (SI) popularly known as the 'wisdom of the crowd'. However, this requires independent estimates (rare in the real world owing to the availability of public information) and contradicts people's bias for copying successful individuals. To explain these inconsistencies, 429 people took part in a 'guess the number of sweets' exercise. Guesses made with no public information were diverse, resulting in highly accurate SI. Individuals with access to the previous guess, mean guess or a randomly chosen guess, tended to over-estimate the number of sweets and this undermined SI. However, when people were provided with the current best guess, this prevented very large (inaccurate) guesses, resulting in convergence of guesses towards the true value and accurate SI across a range of group sizes. Thus, contrary to previous work, we show that social influence need not undermine SI, especially where individual decisions are made sequentially and then aggregated. Furthermore, we offer an explanation for why people have a bias to recruit and follow experts in team settings: copying successful individuals can enable accuracy at both the individual and group level, even at small group sizes.

个体层面的专业知识多样性可以提高集体层面的智力——一种群体智能（SI），通常被称为“群体智慧”。然而，这需要独立的估计（由于公共信息的存在，在现实世界中很少见），并且与人们模仿成功个体的倾向相矛盾。为了解释这些不一致之处，429人参加了一项“猜糖果数量”的活动。在没有公共信息的情况下做出的猜测是多样的，从而产生了高度准确的群体智能。能够获取之前的猜测、平均猜测或随机选择的猜测的个体，往往会高估糖果的数量，这削弱了群体智能。然而，当人们得到当前的最佳猜测时，这避免了非常大（不准确）的猜测，使得猜测在不同的群体规模下都趋向于真实值，从而产生准确的群体智能。因此，与之前的研究相反，我们表明社会影响不一定会削弱群体智能，特别是在个体决策依次做出然后汇总的情况下。此外，我们对为什么人们在团队环境中有招募和追随专家的倾向提供了一种解释：模仿成功个体可以在个体和群体层面都实现准确性，即使是在较小的群体规模下。