English

The Renyi-Ulam pathological liar game with a fixed number of lies

Combinatorics 2010-11-12 v2

Abstract

The qq-round Renyi-Ulam pathological liar game with kk lies on the set [n]:={1,...,n}[n]:=\{1,...,n\} is a 2-player perfect information zero sum game. In each round Paul chooses a subset A[n]A\subseteq [n] and Carole either assigns 1 lie to each element of AA or to each element of [n]A[n]\setminus A. Paul wins if after qq rounds there is at least one element with kk or fewer lies. The game is dual to the original Renyi-Ulam liar game for which the winning condition is that at most one element has kk or fewer lies. We prove the existence of a winning strategy for Paul to the existence of a covering of the discrete hypercube with certain relaxed Hamming balls. Defining Fk(q)F^*_k(q) to be the minimum nn such that Paul can win the qq-round pathological liar game with kk lies and initial set [n][n], we find F1(q)F^*_1(q) and F2(q)F^*_2(q) exactly. For fixed kk we prove that Fk(q)F_k^*(q) is within an absolute constant (depending only on kk) of the sphere bound, 2q/(qk)2^q/\binom{q}{\leq k}; this is already known to hold for the original Renyi-Ulam liar game due to a result of J. Spencer.

Keywords

Cite

@article{arxiv.math/0407504,
  title  = {The Renyi-Ulam pathological liar game with a fixed number of lies},
  author = {Robert B. Ellis and Vadim Ponomarenko and Catherine H. Yan},
  journal= {arXiv preprint arXiv:math/0407504},
  year   = {2010}
}

Comments

18 pages, 1 figure * Typo corrected in Definition 17. * Reference information completed for reference [4]