Symbolic verification of multiagent graphical decision models

Abstract

Multiply sectioned influence diagrams (MSID), together with hyper relevance graph (HRG), is a probabilistic graphical decision model representing distributed decision problems involving multiple agents. To ensure a valid model representation, an MSID observes a set of constraints that must be verified before its evaluation. We present a symbolic method to verify some constraints of this graphical decision model in a cooperative fashion. The method makes full use of an algebraic description of factorization joint probability in an MSID instead of focusing on the graphical structure of decision model. It is a cooperative verification that protects agent's privacy in multiagent systems. Furthermore, the issue of verification failure is investigated with some helpful corrections. Finally, a pairwise verification is proposed concerning other constraints to realize a valid model associated with the knowledge domain. © 2008 Wiley Periodicals, Inc.