## Annals of Applied Probability

### Evolving voter model on dense random graphs

#### Abstract

In this paper, we examine a variant of the voter model on a dynamically changing network where agents have the option of changing their friends rather than changing their opinions. We analyse, in the context of dense random graphs, two models considered in Durrett et al. [Proc. Natl. Acad. Sci. USA 109 (2012) 3682–3687]. When an edge with two agents holding different opinion is updated, with probability $\frac{\beta }{n}$, one agent performs a voter model step and changes its opinion to copy the other, and with probability $1-\frac{\beta }{n}$, the edge between them is broken and reconnected to a new agent chosen randomly from (i) the whole network (rewire-to-random model) or, (ii) the agents having the same opinion (rewire-to-same model). We rigorously establish in both the models, the time for this dynamics to terminate exhibits a phase transition in the model parameter $\beta$. For $\beta$ sufficiently small, with high probability the network rapidly splits into two disconnected communities with opposing opinions, whereas for $\beta$ large enough the dynamics runs for longer and the density of opinion changes significantly before the process stops. In the rewire-to-random model, we show that a positive fraction of both opinions survive with high probability.

#### Article information

Source
Ann. Appl. Probab., Volume 27, Number 2 (2017), 1235-1288.

Dates
Revised: April 2016
First available in Project Euclid: 26 May 2017

https://projecteuclid.org/euclid.aoap/1495764378

Digital Object Identifier
doi:10.1214/16-AAP1230

Mathematical Reviews number (MathSciNet)
MR3655865

Zentralblatt MATH identifier
1368.60095

#### Citation

Basu, Riddhipratim; Sly, Allan. Evolving voter model on dense random graphs. Ann. Appl. Probab. 27 (2017), no. 2, 1235--1288. doi:10.1214/16-AAP1230. https://projecteuclid.org/euclid.aoap/1495764378

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