This paper presents the French version of the SUNDIAL speech understanding and dialogue system, which deals with flight enquiry and reservation over the telephone network.
The system is divided into three main components. The speech recognizer uses hidden Markov models for the French phonemes, and a limited set of triphones and words of special importance for the application. The speech recognizer is connected to a linguistic analyzer, which parses a lattice of words and returns the best grammatical path. The core of the system is a dialogue manager which controls the progress of the dialogue, drives the understanding and answering interfaces, and accesses the flight database. It handles various dialogue phenomena, like confirmations, contestations, over-informative answers, repetition requests.
At the end of the project, the system has been tested on a set of semi-naive users. Evaluation results, indicating a 70% understanding rate and 60% transaction success, are presented in this paper. A qualitative analysis of these results is given.
Bibliographic reference. Magadur, Jean-Yves / Gavignet, Frédéric / Andry, Francois / Charpentier, Francis (1993): "A French oral dialogue system for flight reservations over the telephone", In EUROSPEECH'93, 1789-1792.