Coordination of Decisions in a Spatial Model of Brownian Agents

Brownian agents denote a particular class of heterogeneous agents that combines features of reactive and reflexive agent concepts. As one major advance, the Brownian agent concept allows the derivation of macroscopic equations from the agent dynamics, which can be used to analyze and predict the behavior of the MAS. As an application of the concept, we discuss a binary choice problem where individual decisions are based on different local information generated by the agents. The spatial coordination of decisions in a multi-agent community is investigated both analytically and by means of stochastic computer simulations. We find that dependent on two essential parameters describing the local impact and the spatial dissemination of information either a definite stable minority/majority relation (single-attractor regime) or a broad range of possible values (multi-attractor regime) occurs. In the latter case, the outcome of the decision process becomes rather diverse and hard to predict, both with respect to the fraction of the majority and their spatial distribution. We also show that a more “efficient” information dissemination of a subpopulation provides a suitable way to stabilize their majority status and to reduce “diversity” and uncertainty in the decision process.

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