Chacoma Andrés, Zanette Damián H
Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche and Instituto Balseiro, Comisión Nacional de Energía Atómica, 8400 San Carlos de Bariloche, Río Negro, Argentina.
PLoS One. 2015 Oct 30;10(10):e0140406. doi: 10.1371/journal.pone.0140406. eCollection 2015.
Predicting different forms of collective behavior in human populations, as the outcome of individual attitudes and their mutual influence, is a question of major interest in social sciences. In particular, processes of opinion formation have been theoretically modeled on the basis of a formal similarity with the dynamics of certain physical systems, giving rise to an extensive collection of mathematical models amenable to numerical simulation or even to exact solution. Empirical ground for these models is however largely missing, which confine them to the level of mere metaphors of the real phenomena they aim at explaining. In this paper we present results of an experiment which quantifies the change in the opinions given by a subject on a set of specific matters under the influence of others. The setup is a variant of a recently proposed experiment, where the subject's confidence on his or her opinion was evaluated as well. In our realization, which records the quantitative answers of 85 subjects to 20 questions before and after an influence event, the focus is put on characterizing the change in answers and confidence induced by such influence. Similarities and differences with the previous version of the experiment are highlighted. We find that confidence changes are to a large extent independent of any other recorded quantity, while opinion changes are strongly modulated by the original confidence. On the other hand, opinion changes are not influenced by the initial difference with the reference opinion. The typical time scales on which opinion varies are moreover substantially longer than those of confidence change. Experimental results are then used to estimate parameters for a dynamical agent-based model of opinion formation in a large population. In the context of the model, we study the convergence to full consensus and the effect of opinion leaders on the collective distribution of opinions.
预测人群中不同形式的集体行为，作为个体态度及其相互影响的结果，是社会科学中一个备受关注的问题。特别是，意见形成过程已基于与某些物理系统动力学的形式相似性进行了理论建模，从而产生了大量适用于数值模拟甚至精确求解的数学模型。然而，这些模型在很大程度上缺乏实证依据，这使得它们仅停留在旨在解释的真实现象的隐喻层面。在本文中，我们展示了一项实验的结果，该实验量化了在他人影响下，个体对一组特定问题给出的意见变化。实验设置是最近提出的一个实验的变体，其中还评估了受试者对自己意见的信心。在我们的实验中，记录了85名受试者在影响事件前后对20个问题的定量回答，重点在于刻画这种影响所导致的答案和信心的变化。文中强调了与该实验先前版本的异同。我们发现，信心变化在很大程度上独立于任何其他记录的量，而意见变化则受到原始信心的强烈调节。另一方面，意见变化不受与参考意见的初始差异的影响。此外，意见变化的典型时间尺度比信心变化的时间尺度长得多。然后，实验结果被用于估计基于主体的大群体意见形成动力学模型的参数。在模型的背景下，我们研究了向完全共识的收敛以及意见领袖对意见集体分布的影响。
