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 fi eld trial carried out to assess the technical adequacy of available sp eech technology for interactive services. The data collection system u sed to carry out the field trials is based on the LIMSI Mask spoken la nguage system and runs on a Unix workstation with a high quality telep hone interface. The spoken language system allows a mixed-initiative d ialog 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 us ers tend to provide shorter responses, allowing the system to guide th em. The RailTel field trial was carried out using a common methodology defined by the consortium. 100 novice subjects participated in the fi eld trials, each calling the system one time and completing a user que stionnaire. Of the callers, 72% successfully completed their scenario. The subjective assessment of the prototype was for the most part favo urable, with subjects expressing an interest in using such a service. (C) 1997 Elsevier Science B.V.