Opinion formation analysis for Expressed and Private Opinions (EPOs) models: Reasoning private opinions from behaviors in group decision-making systems

Abstract

In group decision-making, the expressed opinion of a social individual may be inconsistent with or even opposite to his/her own private opinion or inner thought. Expressed and private opinions (EPOs) models were then developed to study decision-making mechanisms with private opinions. However, most of the existing EPOs models assumed that the individual private opinion is often fixed, or updated by his/her own private opinion and neighbors’ expressed opinions, ignoring the behavior characteristics of social individuals. In this paper, a novel EPOs model is built under a more realistic scenario where the individual private opinions are updated by reasoning the neighbors’ private opinions from their behaviors while the expressed opinions are subject to social pressure. Meanwhile, we investigate the group opinion formation under the proposed EPOs model over a Leader–Influencer–Follower hierarchical network. The evolution process under the proposed EPOs model shows that, on the one hand, when the social pressure is monotonically increasing, group expressed opinions often reach consensus, and the consensus reaching time is closely related to the pressure increase rate. On the other hand, group private opinions and behaviors of the individuals show polarization. The simulation results reveal the sociological phenomena of “the golden mean” and “inconsistent words and deeds”, respectively.