The LIMSI RailTel system: Field trial of a telephone service for rail travel information

This paper describes the RailTel system developed at LIMSI to provide vocal access to static train timetable information in French, and a field trial carried out to assess the technical adequacy of available speech technology for interactive services. The data collection system used to carry out the field trials is based on the LIMSI Mask spoken language system and runs on a Unix workstation with a high quality telephone interface. The spoken language system allows a mixed-initiative dialog where the user can provide any information at any point in time. Experienced users are thus able to provide all the information needed for database access in a single sentence, whereas less experienced users tend to provide shorter responses, allowing the system to guide them. The RailTel field trial was carried out using a common methodology defined by the consortium. 100 novice subjects participated in the field trials, each calling the system one time and completing a user questionnaire. Of the callers, 72% successfully completed their scenario. The subjective assessment of the prototype was for the most part favourable, with subjects expressing an interest in using such a service. (C) 1997 Elsevier Science B.V.