School of Biological Sciences, University of Bristol, Bristol, United Kingdom.
Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid, Spain.
PLoS One. 2018 Sep 24;13(9):e0204462. doi: 10.1371/journal.pone.0204462. eCollection 2018.
How effective groups are in making decisions is a long-standing question in studying human and animal behaviour. Despite the limited social and cognitive abilities of younger people, skills which are often required for collective intelligence, studies of group performance have been limited to adults. Using a simple task of estimating the number of sweets in jars, we show in two experiments that adolescents at least as young as 11 years old improve their estimation accuracy after a period of group discussion, demonstrating collective intelligence. Although this effect was robust to the overall distribution of initial estimates, when the task generated positively skewed estimates, the geometric mean of initial estimates gave the best fit to the data compared to other tested aggregation rules. A geometric mean heuristic in consensus decision making is also likely to apply to adults, as it provides a robust and well-performing rule for aggregating different opinions. The geometric mean rule is likely to be based on an intuitive logarithmic-like number representation, and our study suggests that this mental number scaling may be beneficial in collective decisions.
群体在决策方面的有效性是人类和动物行为研究中的一个长期问题。尽管年轻人的社交和认知能力有限，但他们通常需要具备集体智慧所需的技能，然而，群体表现的研究仅限于成年人。我们使用一个简单的任务，即估计罐子中的糖果数量，通过两项实验表明，至少 11 岁的青少年在经过一段时间的小组讨论后，他们的估计准确性会提高，这证明了他们具有集体智慧。尽管这种效果不受初始估计的总体分布的影响，但当任务产生正偏态估计时，与其他测试的聚合规则相比，初始估计的几何平均值更能拟合数据。在共识决策中，几何平均值启发式方法也可能适用于成年人，因为它为聚合不同意见提供了一种稳健且表现良好的规则。几何平均值规则可能基于直观的对数式数字表示，我们的研究表明，这种心理数字标度在集体决策中可能是有益的。
