Speech and Multimodal Dialogue Systems for

This paper describes work on speech dialogue systems for use via telephone access. One of the activities at FTW is to improve the performance of the automatic speech recognition in such systems by tailoring the speech training data, and thereby the recognition models, to Austrian user groups. Speechdat-AT, a telephone speech database of Austrian German, has been developed which has enabled a reduction of recognition errors by a third compared to a recogniser trained on German data. We also describe the Postal rate Dialogue System developed at FTW, which apart from its realworld usefulness serves as an evaluation platform for our telephony dialogue systems research. Finally we present ongoing research that investigates the integration of speech interfaces with other modalities such as pen input and addresses issues of software architecture

The 2003 Isl Rich Transcription System For Conversational

This paper describes the ISL large vocabulary conversational telephony speech recognition system, which was tested in NIST's RT-03S ("Switchboard") evaluation. We present our experiments on improving preprocessing, acoustic modelling, and language modelling. The system features phone dependent semi-tied full covariances, semi-tied clustering of septa-phones, clustering across phones, feature adaptive training, robust estimation of VTLN and MLLR, as well as context dependent interpolation of language models. We present detailed results for each stage of our multipass transcription scheme. System development started in 2002 with an error rate of 35.1% on our internal 1h development set. The final system performed at WER 21.8%, a 38% relative improvement. The error rate on the RT-03 CTS evaluation set is 23.4%

Default handling in incremental generation

Natural language generation must work with insufficient input. Underspecifications can be caused by shortcomings of the component providing the input or by the preliminary state of incrementally given input. The paper aims to escape from such dead-end situations by making assumptions. We discuss global aspects of default handling. Two problem classes for defaults in the incremental syntactic generator VM-GEN are presented to substantiate our discussion. (orig.)SIGLEAvailable from TIB Hannover: RR 5221(22)+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman