Truth seekers in opinion dynamics models

We modify the model of Deffuant et al. to distinguish true opinion among others in the fashion of Hegselmann and Krause . The basic features of both models modified to account for truth seekers are qualitatively the same.Comment: RevTeX4, 2 pages, 1 figure in 6 eps file

The Importance of Disagreeing: Contrarians and Extremism in the CODA model

In this paper, we study the effects of introducing contrarians in a model of Opinion Dynamics where the agents have internal continuous opinions, but exchange information only about a binary choice that is a function of their continuous opinion, the CODA model. We observe that the hung election scenario still exists here, but it is weaker and it shouldn't be expected in every election. Finally, we also show that the introduction of contrarians make the tendency towards extremism of the original model weaker, indicating that the existence of agents that prefer to disagree might be an important aspect and help society to diminish extremist opinions.Comment: 14 pages, 9 figure

Advertising, consensus, and ageing in multilayer Sznajd model

In the Sznajd consensus model on the square lattice, two people who agree in their opinions convince their neighbours of this opinion. We generalize it to many layers representing many age levels, and check if still a consensus among all layers is possible. Advertising sometimes but not always produces a consensus on the advertised opinion.Comment: 6 pages including 4 figures, for Int. J. Mod. Phys.

Monte Carlo simulations of the Ising and the Sznajd model on growing Barabasi - Albert networks

The Ising model shows on growing Barabasi - Albert networks the same ferromagnetic behavior as on static Barabasi - Albert networks. Sznajd models on growing Barabasi - Albert networks show an hysteresis like behavior. Nearly a full consensus builds up and the winning opinion depends on history. On slow growing Barabasi - Albert networks a full consensus builds up. At five opinions in the Sznajd model with limited persuasion on growing Barabasi - Albert networks, all odd opinions win and all even opinions loose supporters.Comment: 6 pages including 3 figures, for IJMP

About the Power to Enforce and Prevent Consensus by Manipulating Communication Rules

We explore the possibilities of enforcing and preventing consensus in continuous opinion dynamics that result from modifications in the communication rules. We refer to the model of Weisbuch and Deffuant, where $n$ agents adjust their continuous opinions as a result of random pairwise encounters whenever their opinions differ not more than a given bound of confidence \eps. A high \eps leads to consensus, while a lower \eps leads to a fragmentation into several opinion clusters. We drop the random encounter assumption and ask: How small may \eps be such that consensus is still possible with a certain communication plan for the entire group? Mathematical analysis shows that \eps may be significantly smaller than in the random pairwise case. On the other hand we ask: How large may \eps be such that preventing consensus is still possible? In answering this question we prove Fortunato's simulation result that consensus cannot be prevented for \eps>0.5 for large groups. % Next we consider opinion dynamics under different individual strategies and examine their power to increase the chances of consensus. One result is that balancing agents increase chances of consensus, especially if the agents are cautious in adapting their opinions. However, curious agents increase chances of consensus only if those agents are not cautious in adapting their opinions.Comment: 21 pages, 6 figure

Continuous Opinions and Discrete Actions in Opinion Dynamics Problems

A model where agents show discrete behavior regarding their actions, but have continuous opinions that are updated by interacting with other agents is presented. This new updating rule is applied to both the voter and Sznajd models for interaction between neighbors and its consequences are discussed. The appearance of extremists is naturally observed and it seems to be a characteristic of this model.Comment: 10 pages, 4 figures, minor changes for improved clarit

Opinion dynamics and decision of vote in bipolar political systems

A model of the opinion dynamics underlying the political decision is proposed. The analysis is restricted to a bipolar scheme with a possible third political area. The interaction among voters is local but the final decision strongly depends on global effects such as, for example, the rating of the governments. As in the realistic case, the individual decision making process is determined by the most relevant personal interests and problems. The phenomenological analysis of the national vote in Italy and Germany has been carried out and a prediction of the next Italian vote as a function of the government rating is presented.Comment: 8 pages, 1 figure. To be published in International Journal of Modern Physics

A dual modelling of evolving political opinion networks

We present the result of a dual modeling of opinion network. The model complements the agent-based opinion models by attaching to the social agent (voters) network a political opinion (party) network having its own intrinsic mechanisms of evolution. These two sub-networks form a global network which can be either isolated from or dependent on the external influence. Basically, the evolution of the agent network includes link adding and deleting, the opinion changes influenced by social validation, the political climate, the attractivity of the parties and the interaction between them. The opinion network is initially composed of numerous nodes representing opinions or parties which are located on a one dimensional axis according to their political positions. The mechanism of evolution includes union, splitting, change of position and of attractivity, taken into account the pairwise node interaction decaying with node distance in power law. The global evolution ends in a stable distribution of the social agents over a quasi-stable and fluctuating stationary number of remaining parties. Empirical study on the lifetime distribution of numerous parties and vote results is carried out to verify numerical results

Time dependence of the survival probability of an opinion in a closed community

The time dependence of the survival probability of an opinion in a closed community has been investigated in accordance with social temperature by using the Kawasaki-exchange dynamics based on previous study in Ref. [1]. It is shown that the survival probability of opinion decays with stretched exponential law consistent with previous static model. However, the crossover regime in the decay of the survival probability has been observed in this dynamic model unlike previous model. The decay characteristics of both two regimes obey to stretched exponential.Comment: Revised version of the paper (9 page, 5 Figures). Submitted to Int. J. Mod. Phys.