7 research outputs found
Phase transitions in a two parameter model of opinion dynamics with random kinetic exchanges
Recently, a model of opinion formation with kinetic exchanges has been
proposed in which a spontaneous symmetry breaking transition was reported [M.
Lallouache et al, Phys. Rev. E, {\bf 82} 056112 (2010)]. We generalise the
model to incorporate two parameters, , to represent conviction and
, to represent the influencing ability of individuals. A phase boundary
given by is obtained separating the symmetric and symmetry
broken phases: the effect of the influencing term enhances the possibility of
reaching a consensus in the society. The time scale diverges near the phase
boundary in a power law manner. The order parameter and the condensate also
show power law growth close to the phase boundary albeit with different
exponents. Theexponents in general change along the phase boundary indicating a
non-universality. The relaxation times, however, become constant with
increasing system size near the phase boundary indicating the absence of any
diverging length scale. Consistently, the fluctuations remain finite but show
strong dependence on the trajectory along which it is estimated.Comment: Version accepted for PRE; text modified, new figures and references
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Opinion dynamics: rise and fall of political parties
We analyze the evolution of political organizations using a model in which
agents change their opinions via two competing mechanisms. Two agents may
interact and reach consensus, and additionally, individual agents may
spontaneously change their opinions by a random, diffusive process. We find
three distinct possibilities. For strong diffusion, the distribution of
opinions is uniform and no political organizations (parties) are formed. For
weak diffusion, parties do form and furthermore, the political landscape
continually evolves as small parties merge into larger ones. Without diffusion,
a pattern develops: parties have the same size and they possess equal niches.
These phenomena are analyzed using pattern formation and scaling techniques.Comment: 5 pages, 5 figure
Opinion and community formation in coevolving networks
In human societies opinion formation is mediated by social interactions,
consequently taking place on a network of relationships and at the same time
influencing the structure of the network and its evolution. To investigate this
coevolution of opinions and social interaction structure we develop a dynamic
agent-based network model, by taking into account short range interactions like
discussions between individuals, long range interactions like a sense for
overall mood modulated by the attitudes of individuals, and external field
corresponding to outside influence. Moreover, individual biases can be
naturally taken into account. In addition the model includes the opinion
dependent link-rewiring scheme to describe network topology coevolution with a
slower time scale than that of the opinion formation. With this model
comprehensive numerical simulations and mean field calculations have been
carried out and they show the importance of the separation between fast and
slow time scales resulting in the network to organize as well-connected small
communities of agents with the same opinion.Comment: 10 pages, 5 figures. New inset for Fig. 1 and references added.
Submitted to Physical Review
Kinetic exchange opinion model: solution in the single parameter map limit
We study a recently proposed kinetic exchange opinion model (Lallouache et.
al., Phys. Rev E 82:056112, 2010) in the limit of a single parameter map.
Although it does not include the essentially complex behavior of the multiagent
version, it provides us with the insight regarding the choice of order
parameter for the system as well as some of its other dynamical properties. We
also study the generalized two- parameter version of the model, and provide the
exact phase diagram. The universal behavior along this phase boundary in terms
of the suitably defined order parameter is seen.Comment: 14 pages, 9 figure