Opinion dynamics under the influence of radical groups, charismatic leaders, and other constant signals: A simple unifying model

Abstract

By a simple extension of the bounded confidence model, it is possible to model the in uence of a radical group, or a charismatic leader on the opinion dynamics of 'normal' agents that update their opinions under both, the in uence of their normal peers, and the additional in uence of the radical group or a charismatic leader. From a more abstract point of view, we model the in uence of a signal, that is constant, may have different intensities, and is 'heard' only by agents with opinions, that are not too far away. For such a dynamic a Constant Signal Theorem is proven. In the model we get a lot of surprising effects. For instance, the more intensive signal may have less effect; more radicals may lead to less radicalization of normal agents. The model is an extremely simple conceptual model. Under some assumptions the whole parameter space can be analyzed. The model inspires new possible explanations, new perspectives for empirical studies, and new ideas for prevention or intervention policies.