Volker Warnke

Learn More
This paper presents automatic methods for the segmenta-tion and classication of dialog acts (DA). In Verbmobil it is often sucient to recognize the sequence of DAs occurring during a dialog between the two partners. Since a turn can consist of one or more successive D As we conduct the classication of DAs in a two step procedure: First each turn has to be(More)
Nowadays modern automatic dialogue systems are able to understand complex sentences instead of only a few commands like Stop or No. In a call-center, such a system should be able to determine in a critical phase of the dialogue if the call should be passed over to a human operator. Such a critical phase can be indicated by the customer's vocal expression.(More)
This paper presents an integrated approach for the segmentation and classiication of dialog acts DA in the Verbmobil project. In Verbmobil it is often suucient to recognize the sequence of DAs occurring during a dialog between the two partners. In our previous work 55 we segmented and classiied a dialog in two steps: rst we calculated hypotheses for the(More)
In the focus of this paper is a comparison of the most relevant prosodic features/feature classes for the classification of boundaries and accents in German and in English. Principal components were computed based on a large prosodic feature vector ; these principal components were used as predictor variables in a Linear Discriminant analysis as well as in(More)
In this paper we present a new approach for estimating the interpolation parameters of language models (LM) which are used as classifiers. With the classical maximum likelihood (ML) estimation theoretically one needs to have a huge amount of data and the fundamental density assumption has to be correct. Usually one of these conditions is violated, so(More)
In this paper, we show how prosodic information can be used in automatic dialogue systems and give some examples of promising new approaches. Most of these examples are taken from our own work in the VERBMOBIL speech–to–speech translation system and the EVAR train timetable dialogue system. In a 'prosodic orbit', we first present units, phenomena,(More)
In our paper, we address the problem of estimating stochastic language models based on n-gram statistics. We present a novel approach, rational interpolation, for the combination of a competing set of conditional n-gram word probability predictors, which consistently outper-forms the traditional linear interpolation scheme. The superiority of rational(More)
During the last years, we have been working on the automatic classiication of boundaries and accents in the German VERBMOBIL VM project human-human communication, appointment scheduling dialogues. A sub-corpus was annotated manually with prosodic boundary and accent labels, and neural networks NN trained with a large set of prosodic features were used for(More)
Linguistic processing in spoken dialogue systems has to be robust against a large number of phenomena such as recognizer errors, spontaneous speech phenomena and out-of-vocabulary OOV words. A commonly used solution to this problem is partial parsing, that aims at detecting only parts of sentencessutterances that are vital for the respective task of the(More)