Heterogeneous transformation of uncertainties of propositions among inexact reasoning models

Cooperation between different expert systems within a heterogeneous distributed expert system is essentially based on the transformations between the reasoning models built into the structures of the involved systems. The general criteria for a transformation between heterogeneous inexact reasoning models have been formulated. Using an algebraic structure of semigroup (with individual unit elements) of inexact reasoning models, the criteria are natural and easily satisfied by homomorphic mapping as an implementation. The criteria presented are too weak to ensure the existence of a unique mapping between the models concerned, but they are strong enough to guarantee reasonable transformations. These general considerations are illustrated using the example of three inexact reasoning models used by EMYCIN, PROSPECTOR, and MYCIN, where the homomorphic transformations among them are constructed and discussed