Properties of zero-determinant strategies in multichannel games
Masahiko Ueda
TL;DR
This work extends zero-determinant (ZD) payoff-control theory to multichannel repeated games, showing that the existence of ZD strategies in a multichannel game is tightly constrained by the structure of each channel. The authors derive an autocratic condition that decomposes additively across channels, revealing that MC ZD strategies exist only when channel-wise conditions can be satisfied (and may fail even if some channels do not admit ZD. They prove that nontrivial equalizer strategies in MC require their existence in at least one channel, and that fair ZD strategies in MC necessitate fairness in every channel. The paper provides concrete examples, including multichannel prisoner’s dilemma and combined games, to illustrate how equalizers can emerge through channel interactions and to establish limits on the prevalence of MC ZD strategies. These results have implications for understanding and engineering payoff control and cooperation in systems where agents participate in multiple parallel interactions.
Abstract
Controlling payoffs in repeated games is one of the important topics in control theory of multi-agent systems. Recently proposed zero-determinant strategies enable players to unilaterally enforce linear relations between payoffs. Furthermore, based on the mathematics of zero-determinant strategies, regional payoff control, in which payoffs are enforced into some feasible regions, has been discovered in social dilemma situations. More recently, theory of payoff control was extended to multichannel games, where players parallelly interact with each other in multiple channels. However, the existence of payoff-controlling strategies in multichannel games seems to require the existence of payoff-controlling strategies in some channels, and properties of zero-determinant strategies specific to multichannel games are still not clear. In this paper, we elucidate properties of zero-determinant strategies in multichannel games. First, we relate the existence condition of zero-determinant strategies in multichannel games to that of zero-determinant strategies in each channel. We then show that the existence of zero-determinant strategies in multichannel games requires the existence of zero-determinant strategies in some channels. This result implies that the existence of zero-determinant strategies in multichannel games is tightly restricted by structure of games played in each channel.
