Token system stability linked to community service constraints
When do token systems stabilize? Compatibility constraints and community structure
Computer Science and Game Theory
Summary
Token systems let people exchange services without money by keeping track of tokens, but these systems only work well if token balances stay steady over time. The authors study when such systems remain stable, especially when agents have limits on who can serve whom. They find a clear rule for stability and show that choosing to serve the person with the fewest tokens helps keep the system stable. They also analyze random community structures to understand what can make these systems fail, such as lack of enough service chances for some groups or individuals.
What this means in practice
- •For platform designers: Design service exchange platforms with token rules that keep balances and interactions stable over time.
- •For online community managers: Identify community groups at risk of service breakdown due to limited opportunities by applying stability criteria to community structures.
Tested on simulated data.
Authors
Flore Sentenac, Mingwei Yang, Sophie H. Yu
Abstract
Token systems support repeated service exchange without monetary transfers, but their viability depends on the stability of token balances. We study token systems with compatibility constraints among agents. A requester is randomly sampled in each period, and only a few randomly sampled agents are available to provide service. We establish a necessary and sufficient condition for stability and show that the minimum-token rule, which selects the available provider with the lowest token balance, achieves the optimal stability region. We then apply this stability criterion to a random token system generated from stochastic block models with uniformly sampled requesters. We tightly characterize the stability regime by identifying two obstructions to stability: insufficient service opportunities for a group of communities or for an individual agent.