Computer-aided Design/analysis for Chinese Spoken Dialogue Systems

Conventionally design principles for spoken dialogue systems are drawn either from experiences or from corpus-based analysis. However, human experiences are usually not precise enough for engineering design, while for corpus-based analysis many factors such as speech recognition or understanding performance and user’s behavior can never be precisely controlled. Recently, a new design/analysis approach by computer simulation was proposed. This paper presents the experiences of using this approach to design Chinese spoken dialogue systems. The simulation indicated the following observations and design principles. The transaction success rate (reliability) and slot transmission efficiency (efficiency) are usually conflicting design goals, and trade-off between them thus exists. Since reliability is more important than efficiency in general, it is desirable to achieve higher reliability at the price of reduced slot transmission efficiency when the reliability is not adequate. According to the simulation results, when the speech recognition accuracy cannot be improved, there still exists limited flexibility for tuning the dialogue performance by selecting among the strategies and considering the trade-offs. It is not only possible to select among the strategies considering the design goals, but to estimate the gain obtained and the price paid in the selection. New dialogue strategies can also be designed and numerically verified in this way.