This paper reports the design of a Wizard of Oz simulation of a spoken dialogue system in the context of a telephone directory information service. The experiment described here was carried out within the framework of a Belgian Telecom R&D project, the aim of which is to develop a prototype system for the automatic handling of directory information queries with voice input/output facilities. The authors' task in the project consists in designing the information dialogue models which will be used in the eventual prototype. The target application is the database of the Belgian Telecom Information Centre. The authors advocate some crucial methodological choices, which clearly distinguish this experiment from most current alternative approaches. The dialogue analysis is discussed and conclusions are drawn, the focus being on (i) the adequacy of the methodology to the design of dialogue models, (ii) the pertinence of such models in an automated environment, and (Hi) the evaluation of the dialogue sessions by the subjects.
Keywords: Spoken dialogue, Wizard of Oz experiment, human factors.