Field trial evaluations of two different information inquiry systems

Abstract This paper presents the evaluations of the field trials of two information inquiry systems that use different speech technologies and different human–machine interfaces. The first system, RAILTEL, uses isolated word recognition and system driven dialogue. The second system, Dialogos, understands spontaneous speech and implements a mixed initiative dialogue strategy. Both systems allow access to the Italian Railway timetable by using the telephone over the public network. RAILTEL and Dialogos were tested in extensive field trials by inexperienced subjects. Moreover, a comparative trial with a limited number of subjects was performed in order to gain some insights on the impact of the different speech technologies on users' behaviour. The paper will provide a brief description of the two systems, details of the experimental set up of the trials, and the discussion of the results.