The Cost of Communication: Efficient Coordination in Multi-agent Territory Exploration Tasks

Some previous studies of the adaptiveness of communication for behavior coordination have found that communication is beneficial and, therefore, will evolve. Others point out shortcomings in prior studies with positive results and find that when those shortcomings are addressed, communication no longer will evolve for coordination. It appears, however, that communication has evolved for coordination, which suggests that those studies with negative findings also are missing some key factor. None of these studies undertakes a systematic examination of important variables such as communication range, sensory range, and environmental conditions. To address this shortcoming, an extensive series of simulations is presented that explore the effect of such parameters on the utility of communication for coordinating agent behaviors in the multi-agent territory exploration (MATE(n)) task. Agents in the MATE(n) task are required to visit all checkpoints given in the environment in as little time as possible; n agents are required to be present at a checkpoint simultaneously for it to be counted ``visited.' A comparison of the absolute performance of communicating and non-communicating agents on the MATE(n) task (i.e., their performance without regard to cost) finds that there are configurations in which communication provides an absolute performance advantage. A subsequent analysis of the results establishes constraints on the cost of communication must be satisfied in order for it to provide a benefit in relative performance} (i.e., absolute performance scaled by agent cost), required for communication to evolve. Further analysis determines that these cost constraints are probably too strict, making it unlikely that communication evolved for coordination in MATE(n) tasks.