TOWARDS COMPETENT INFORMATION ACQUISITION INTERACTIONS BETWEEN AN EXPERT-SYSTEM AND ITS USER

Expert systems are consultative, highly interactive systems, and hence the quality of interaction between system and user is important for t he acceptability of the system. Acquisition of data about the problem in hand is a central feature of the interaction between system and use r, and it makes a major contribution to the user's perception of the s ystem. It is therefore crucial that the acquisition of this data (both as individual data items and as a sequence of data inputs) is perceiv ed by the user as competent. This paper identifies central, domain-ind ependent, design goals for the information-acquisition interactions be tween an expert system and its user, including mixed-initiative intera ction, flexibility in user input, and system competence in querying th e user. The paper discusses the realisation of these goals in a diagno stic expert system, Skeletal Dysplasias Diagnostician, through an expl icit data model which allows for the representation of data with tempo ral and spatial (locality) aspects and the decide-status function whic h operates on the data model.