An approach to knowledge acquisition based on the structure of personal construct systems

A research effort aimed at the development and unification of the prerequisite underlying theoretical foundations for an adequate approach to knowledge elicitation from repertory grid data is described. A theory of confirmation that incorporates the basic tenets of personal construct psychology directly into the logic as a basis for the determination of relevance is offered, thus strengthening the logic and extending personal construct psychology. These largely theoretical developments are applied to the representation and analysis of repertory grid data. The concept of an α-plane is introduced as a binary decomposition of repertory grid data that furnishes the realization of construct extensions (or ranges of convenience) needed to determine the range of relevance of a particular generalization or hypothesis. In addition, they provide the uniquely determined string of incidences required by any application of Bundy´s truth functional incidence calculus. The theories are applied to the design and construction of NICOD-a semiautomated medical knowledge acquisition system. The system has been successfully employed in the elicitation of valuable heuristic radiological knowledge (mammography) that the domain experts (radiologists) were otherwise unable to articulate