English

How strong can the Parrondo effect be? II

Probability 2020-01-03 v1

Abstract

Parrondo's coin-tossing games comprise two games, AA and BB. The result of game AA is determined by the toss of a fair coin. The result of game BB is determined by the toss of a p0p_0-coin if capital is a multiple of rr, and by the toss of a p1p_1-coin otherwise. In either game, the player wins one unit with heads and loses one unit with tails. Game BB is fair if (1p0)(1p1)r1=p0p1r1(1-p_0)(1-p_1)^{r-1}=p_0\,p_1^{r-1}. In a previous paper we showed that, if the parameters of game BB, namely rr, p0p_0, and p1p_1, are allowed to be arbitrary, subject to the fairness constraint, and if the two (fair) games AA and BB are played in an arbitrary periodic sequence, then the rate of profit can not only be positive (the so-called Parrondo effect), but also be arbitrarily close to 1 (i.e., 100%). Here we prove the same conclusion for a random sequence of the two games instead of a periodic one, that is, at each turn game AA is played with probability γ\gamma and game BB is played otherwise, where γ(0,1)\gamma\in(0,1) is arbitrary.

Keywords

Cite

@article{arxiv.2001.00291,
  title  = {How strong can the Parrondo effect be? II},
  author = {S. N. Ethier and Jiyeon Lee},
  journal= {arXiv preprint arXiv:2001.00291},
  year   = {2020}
}

Comments

12 pages

R2 v1 2026-06-23T13:00:58.789Z