Vacillating voter model
Vacillating voter model is a generalization of the voter model, which shows that contrarian behavior can emerge from imitative interactions [1]. This result is kind of interesting and counter-intuitive as usually, in other models of opinion dynamics, contrarian behavior is being explicitly built in.
The model
The model is strongly reminiscent of the voter model, yet with a small caveat. If a randomly selected voter has the same opinion as its (first) randomly picked neighbor, he picks another (second) neighbor and adopts its opinion.
This simple change has a profound effect. In case of the original voter model on a square lattice the flip probability is \( \frac{k}{4} \) (where \( k \) is a number of disagreeing neighbors). In this model on a square lattice flip probability is larger: \( 0 \) (for \( k=0 \)), \( \frac{1}{2} \) (for \( k=1 \)), \( \frac{5}{6} \) (for \( k=2 \)) and \( 1 \) (for \( k \geq 3 \)). These vacillating agents more easily succumb to the peer pressure, even if only one neighbor disagrees.
HTML 5 app
This app does not have any parameters besides the probability used during model initialization. Yet feel free to explore consensus times of this simple model.
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Acknowledgment. This post was written while reviewing literature relevant to the planned activities in postdoctoral fellowship ''Physical modeling of order-book and opinion dynamics'' (09.3.3-LMT-K-712-02-0026) project. The fellowship is funded by the European Social Fund under the No 09.3.3-LMT-K-712 ''Development of Competences of Scientists, other Researchers and Students through Practical Research Activities'' measure.
References
- R. Lambiotte, S. Redner. Dynamics of vacillating voters. Journal of Statistical Mechanics 2007: L10001 (2007). doi: 10.1088/1742-5468/2007/10/L10001. arXiv:0710.0914 [physics.soc-ph].