Multi-agent coordination via communication partitions
Wei-Chen Lee, Alessandro Abate, Michael Wooldridge
TL;DR
This work tackles equilibrium selection with multiple Nash equilibria by introducing a partitioned pre-play communication mechanism among coalitions in Singleton Congestion Games (SCGs) with identical resources. By leveraging a symmetry-based epistemic framework, coalitions can reach envy-free, credible, Pareto-optimal agreements that, when aggregated across a balanced partition, yield socially optimal and evenly distributed outcomes. The analysis shows that such partition-induced equilibria are $\bar{c}$-optimal and $\hat{c}$-optimal, and extends to settings with differential resource costs under known distributions. This approach provides a scalable design principle for coordinating decentralized, anonymous resource allocations and informs future work on weighted agents and cost-structure variations.
Abstract
Coordinating the behaviour of self-interested agents in the presence of multiple Nash equilibria is a major research challenge for multi-agent systems. Pre-game communication between all the players can aid coordination in cases where the Pareto-optimal payoff is unique, but can lead to deadlocks when there are multiple payoffs on the Pareto frontier. We consider a communication partition, where only players within the same coalition can communicate with each other, and they can establish an agreement (a coordinated joint-action) if it is envy-free, credible, and Pareto-optimal. We show that under a natural assumption about symmetry, certain communication partitions can induce social optimal outcomes in singleton congestion games. This game is a reasonable model for a decentralised, anonymous system where players are required to choose from a range of identical resources, and incur costs that are increasing and convex in the total number of players sharing the same resource. The communication partition can be seen as a mechanism for inducing efficient outcomes in this context.
