# Passage time of a random walk in the quarter plane for opinions in the voter model

* Corresponding author
1 Modélisation stochastique
LPMA - Laboratoire de Probabilités et Modèles Aléatoires
Abstract : A random walk in $Z_+^2$ spatially homogeneous in the interior, absorbed at the axes, starting from an arbitrary point $(i_0,j_0)$ and with step probabilities drawn on Figure 1 is considered. The trivariate generating function of probabilities that the random walk hits a given point $(i,j)\in Z_+^2$ at a given time $k\geq 0$ is made explicit. Probabilities of absorption at a given time $k$ and at a given axis are found, and their precise asymptotic is derived as the time $k\to\infty$. The equivalence of two typical ways of conditioning this random walk to never reach the axes is established. The results are also applied to the analysis of the voter model with two candidates and initially, in the population $Z$, four connected blocks of same opinions. Then, a citizen changes his mind at a rate proportional to the number of its neighbors that disagree with him. Namely, the passage from four to two blocks of opinions is studied.
Keywords :
Domain :

Cited literature [21 references]

https://hal.archives-ouvertes.fr/hal-00384187
Contributor : Kilian Raschel <>
Submitted on : Thursday, July 4, 2013 - 1:43:28 PM
Last modification on : Saturday, March 28, 2020 - 2:17:10 AM
Document(s) archivé(s) le : Saturday, October 5, 2013 - 4:16:25 AM

### File

4to2blocks.pdf
Files produced by the author(s)

### Citation

Irina Kourkova, Kilian Raschel. Passage time of a random walk in the quarter plane for opinions in the voter model. Queueing Systems, Springer Verlag, 2013, 74 (2-3), pp.219-234. ⟨10.1007/s11134-012-9333-7⟩. ⟨hal-00384187v4⟩

Record views