Verification of DAG structures in cooperative belief network-based multiagent systems

Multiply sectioned Bayesian networks (MSBNs) provide a framework for probabilistic reasoning in a complex single-user-oriented system as well as in a cooperative multiagent distributed interpretation system. During the construction or dynamic formation of an MSBN, automatic verification of the acyclicity of the overall structure is desired. Well-known algorithms for an acyclicity test assume a centralized storage of the structure to be tested. We discuss why a centralized test is undesirable and propose a distributed algorithm that verifies the acyclicity through cooperation among subnets/agents. The algorithm does not require each agent to reveal its internal structure and thus supports construction of an MSBN from subnets built by different vendors. (C) 1998 John Wiley & Sons, Inc.