Time Dependent Biased Random Walks

Saved in:
Bibliographic Details
Title: Time Dependent Biased Random Walks
Authors: John Haslegrave, Thomas Sauerwald, John Sylvester
Contributors: DSpace at Cambridge pro (8.1)
Source: ACM Transactions on Algorithms. 18:1-30
Publication Status: Preprint
Publisher Information: Association for Computing Machinery (ACM), 2022.
Publication Year: 2022
Subject Terms: FOS: Computer and information sciences, Discrete Mathematics (cs.DM), Markov chain, Probability (math.PR), G.3, G.2.2, Random walk, 0102 computer and information sciences, 01 natural sciences, PSPACE, cover time, FOS: Mathematics, Mathematics - Combinatorics, Combinatorics (math.CO), F.2.2, 0101 mathematics, QA, 05C81, 60J10, 68R10, 68Q17, Markov decision process, Mathematics - Probability, Computer Science - Discrete Mathematics
Description: We study the biased random walk where at each step of a random walk a “controller” can, with a certain small probability, move the walk to an arbitrary neighbour. This model was introduced by Azar et al. [STOC’1992]; we extend their work to the time dependent setting and consider cover times of this walk. We obtain new bounds on the cover and hitting times. Azar et al. conjectured that the controller can increase the stationary probability of a vertex from p to p 1-ε ; while this conjecture is not true in full generality, we propose a best-possible amended version of this conjecture and confirm it for a broad class of graphs. We also consider the problem of computing an optimal strategy for the controller to minimise the cover time and show that for directed graphs determining the cover time is PSPACE -complete.
Document Type: Article
File Description: application/pdf
Language: English
ISSN: 1549-6333
1549-6325
DOI: 10.1145/3498848
DOI: 10.48550/arxiv.2006.02475
DOI: 10.17863/cam.82693
Access URL: http://arxiv.org/abs/2006.02475
http://wrap.warwick.ac.uk/160144/1/WRAP-Time-dependent-biased-random-walks-2021.pdf
https://eprints.gla.ac.uk/267876/1/267876.pdf
https://ora.ox.ac.uk/objects/uuid:fcd50914-f2f0-4f0b-a3ee-fc40b5c38b8b
https://doi.org/10.1145/3498848
https://www.repository.cam.ac.uk/handle/1810/335261
https://doi.org/10.17863/cam.82693
https://doi.org/10.1145/3498848
Rights: arXiv Non-Exclusive Distribution
rioxx All Rights Reserved
URL: https://www.acm.org/publications/policies/copyright_policy#Background
Accession Number: edsair.doi.dedup.....72eb70c25210b9b9bc3561ebafa5c5d4
Database: OpenAIRE
Description
Abstract:We study the biased random walk where at each step of a random walk a “controller” can, with a certain small probability, move the walk to an arbitrary neighbour. This model was introduced by Azar et al. [STOC’1992]; we extend their work to the time dependent setting and consider cover times of this walk. We obtain new bounds on the cover and hitting times. Azar et al. conjectured that the controller can increase the stationary probability of a vertex from p to p 1-ε ; while this conjecture is not true in full generality, we propose a best-possible amended version of this conjecture and confirm it for a broad class of graphs. We also consider the problem of computing an optimal strategy for the controller to minimise the cover time and show that for directed graphs determining the cover time is PSPACE -complete.
ISSN:15496333
15496325
DOI:10.1145/3498848