Network-based management of subjective judgements: a proposal accepting cyclic dependencies

The architecture of an uncertainty manager (UM) based on belief revision concepts is proposed. It automatically maintains the consistency of related propositions according to a given theory of uncertainty. Facts are represented as nodes of a network, whose links stand for inferential dependencies among the connected nodes. Each node is associated to a measure of the confidence the UM has in it. The effect of any change in the network is propagated throughout the whole network to preserve consistency. The motivations to accept cyclic dependencies among propositions in such a network are discussed, and the solutions to the problems arising are presented. A theory of uncertainty suitable for representing subjective linguistic estimates is proposed as a solution to the representation of uncertainty coming from subjective judgements. The UM can work with any uncertainty theory whose definition satisfies the general framework presented