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arXiv · 1308.2795

Complex dynamics of a nonlinear voter model with contrarian agents

Shoma Tanabe·Naoki Masuda
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Abstract

We investigate mean-field dynamics of a nonlinear opinion formation model with congregator and contrarian agents. Each agent assumes one of the two possible states. Congregators imitate the state of other agents with a rate that increases with the number of other agents in the opposite state, as in the linear voter model and nonlinear majority voting models. Contrarians flip the state with a rate that increases with the number of other agents in the same state. The nonlinearity controls the strength of the majority voting and is used as a main bifurcation parameter. We show that the model undergoes a rich bifurcation scenario comprising the egalitarian equilibrium, two symmetric lopsided equilibria, limit cycle, and coexistence of different types of stable equilibria with intertwining attrative basins.

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Shoma Tanabe, Naoki Masuda. 2013-12-24. Complex dynamics of a nonlinear voter model with contrarian agents. https://doi.org/10.1063/1.4851175

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