Abstract (EN)

In this article, we propose an agent-based model of opinion diffusion and voting where agents influence each other through deliberation. The model is inspired from social modeling as it describes a process of collective decision-making that iterates on a series of dyadic inter-individual influence steps and collective deliberation procedures. We study the evolution of opinions and the correctness of decisions taken within a group. We also aim at founding a comprehensive model to describe collective decision-making as a combination of two different paradigms: argumentation theory and agent-based influence models, which are not obvious to link since a formal translation and interpretation of their relationship is required. From a sequence of controlled simulations, we find that deliberation, modeled as an exchange of arguments, reduces the variance of opinions and the number of extremists, as long as not too much deliberation takes place during the decision-making process. Insofar as we define “correct” decisions as those whose supporting arguments survive deliberation, promoting deliberative discussion favors convergence towards correct decisions.