Europhys. Lett.
Volume 72, Number 5, December 2005
Page(s) 851 - 857
Section Interdisciplinary physics and related areas of science and technology
Published online 28 October 2005
Europhys. Lett., 72 (5), pp. 851-857 (2005)
DOI: 10.1209/epl/i2005-10299-3

Spontaneous emergence of contrarian-like behaviour in an opinion spreading model

M. S. de la Lama1, 2, J. M. López1 and H. S. Wio1, 3

1  Instituto de Física de Cantabria (IFCA), CSIC-UC - E-39005 Santander, Spain
2  Departamento de Física Moderna, Universidad de Cantabria Avda. Los Castros, E-39005 Santander, Spain
3  Centro Atomico Bariloche and Instituto Balseiro 8400 San Carlos de Bariloche, Argentina

received 2 August 2005; accepted in final form 30 September 2005
published online 28 October 2005

We introduce stochastic driving in the Sznajd model of opinion spreading. This stochastic effect is meant to mimic a social temperature, so that agents can take random decisions with a varying probability. We show that a stochastic driving has a tremendous impact on the system dynamics as a whole by inducing an order-disorder nonequilibrium phase transition. Interestingly, under certain conditions, this stochastic dynamics can spontaneously lead to agents in the system who are analogous to Galam's contarians.

89.65.-s - Social and economic systems.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
64.60.Ht - Dynamic critical phenomena.

© EDP Sciences 2005