• Corpus ID: 7537681

Tight Analysis for the 3-Majority Consensus Dynamics

@article{Ghaffari2017TightAF,
  title={Tight Analysis for the 3-Majority Consensus Dynamics},
  author={Mohsen Ghaffari and Johannes Lengler},
  journal={ArXiv},
  year={2017},
  volume={abs/1705.05583}
}
We present a tight analysis for the well-studied randomized 3-majority dynamics of stabilizing consensus, hence answering the main open question of Becchetti et al. [SODA'16]. Consider a distributed system of n nodes, each initially holding an opinion in {1, 2, ..., k}. The system should converge to a setting where all (non-corrupted) nodes hold the same opinion. This consensus opinion should be \emph{valid}, meaning that it should be among the initially supported opinions, and the (fast… 

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