Article

# Consequence of reputation in the Sznajd

Departamento de Física, I3N – Universidade de Aveiro, 3810-193 Aveiro, Portugal
(Impact Factor: 1.68). 07/2010; 374(34):3380-3383. DOI: 10.1016/j.physleta.2010.06.036
Source: arXiv

ABSTRACT

In this work we study a modified version of the Sznajd sociophysics model. In particular we introduce reputation, a mechanism that limits the capacity of persuasion of the agents. The reputation is introduced as a score which is time-dependent, and its introduction avoid dictatorship (all spins parallel) for a wide range of parameters. The relaxation time follows a log-normal-like distribution. In addition, we show that the usual phase transition also occurs, as in the standard model, and it depends on the initial concentration of individuals following an opinion, occurring at a initial density of up spins greater than 1/2. The transition point is determined by means of a finite-size scaling analysis.

### Full-text

Available from: Fabricio Luchesi Forgerini,
• Source
##### Article: Enforcing social behavior in an Ising model with complex neighborhoods
[Hide abstract]
ABSTRACT: a b s t r a c t We consider the problem of enforcing desired behavior in a population of individuals modeled by an Ising model. Although there is a large literature dealing with social interaction models, the problem of controlling behavior in a system modeled by the Ising model seems to be an unexplored field. First, we provide and analytically characterize an optimal policy that may be used to achieve this objective. Second, we show that complex neighborhoods highly influence the decision making process. Third, we use Lagrange multipliers associated to some constraints of a related problem to identify the role of individuals in the system.
Physica A: Statistical Mechanics and its Applications 05/2011; 390(9):1695-1703. DOI:10.1016/j.physa.2011.01.006 · 1.73 Impact Factor
• Source
##### Article: The Sznajd model with limited persuasion: competition between high-reputation and hesitant agents
[Hide abstract]
ABSTRACT: In this work we study a modified version of the two-dimensional Sznajd sociophysics model. In particular, we consider the effects of agents' reputations in the persuasion rules. In other words, a high-reputation group with a common opinion may convince their neighbors with probability $p$, which induces an increase of the group's reputation. On the other hand, there is always a probability $q=1-p$ of the neighbors to keep their opinions, which induces a decrease of the group's reputation. These rules describe a competition between groups with high reputation and hesitant agents, which makes the full-consensus states (with all spins pointing in one direction) more difficult to be reached. As consequences, the usual phase transition does not occur for $p<p_{c} \sim 0.69$ and the system presents realistic democracy-like situations, where the majority of spins are aligned in a certain direction, for a wide range of parameters.
Journal of Statistical Mechanics Theory and Experiment 08/2011; 11(11). DOI:10.1088/1742-5468/2011/11/P11004 · 2.40 Impact Factor
• Source
##### Article: Effects of mass media on opinion spreading in the Sznajd sociophysics model
[Hide abstract]
ABSTRACT: In this work we consider the influence of mass media in the dynamics of the two-dimensional Sznajd model. This influence acts as an external field, and it is introduced in the model by means of a probability $p$ of the agents to follow the media opinion. We performed Monte Carlo simulations on square lattices with different sizes, and our numerical results suggest a change on the critical behavior of the model, with the absence of the usual phase transition for $p>\sim 0.18$. Another effect of the probability $p$ is to decrease the average relaxation times $\tau$, that are log-normally distributed, as in the standard model. In addition, the $\tau$ values depend on the lattice size $L$ in a power-law form, $\tau\sim L^{\alpha}$, where the power-law exponent depends on the probability $p$.
Physica A: Statistical Mechanics and its Applications 11/2011; 391(4). DOI:10.1016/j.physa.2011.11.038 · 1.73 Impact Factor