Volker Warnke

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This paper presents an integrated approach for the segmentation and classi cation of dialog acts (DA) in the Verbmobil project. In Verbmobil it is often su cient to recognize the sequence of DAs occurring during a dialog between the two partners. In our previous work [5] we segmented and classi ed a dialog in two steps: rst we calculated hypotheses for the(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 automatic methods for the segmentation and classi cation of dialog acts (DA). In Verbmobil it is often su cient to recognize the sequence of DAs occurring during a dialog between the two partners. Since a turn can consist of one or more successive DAs we conduct the classi cation of DAs in a two step procedure: First each turn has to be(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 a(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)
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 this paper we want to bridge the gap between phonetic/phonological theory on the one hand and automatic speech processing on the other hand. As material, we use a subset of the German VERBMOBIL database that is annotated with prosodic boundary and accent information. We computed a large prosodic feature vector: 276 features for a context window of up to(More)
In this paper we report on rst experiments for the detection of emotion and the use of this information in a complex speech understanding system like Verbmobil. We do not look at lexical information like swear words but rather try to nd emotional utterances with the use of acoustic prosodic cues. We only want to classify angry versus neutral speaking style.(More)
For the classification of boundaries and accents in German and English spontaneous speech in the VERBMOBIL project (speech to speech translation system), we use a large prosodic feature vector; duration features represent the most important feature class. They are computed in three different ways: (1) The word duration is normalized with respect to the(More)