Field trial evaluations of two different information inquiry systems

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 a system driven dialogue. The second system, Dialogos, understands spontaneous speech and implements a mixed initiative dialogue strategy. Both systems access the Italian Railway timetable by using the telephone over the public network. Both the systems were tested in extensive field trials by inexperienced subjects. Moreover a comparative trial with a limited number of subjects was performed in order to get some insights on the impact of the use of different speech technologies on the user behaviour. After a brief description of the two systems, the paper reports the details of the experimental set up of the trials and a discussion of the results.