A compositional DRS-based formalism for NLP applications

This paper describes and discusses the formalism which forms the backbone of semantic processing in the Verbmobil spoken dialogue translation project. In the first part, the theoretical core of the formalism is presented: lambda-DRT, a compositional version of Discourse Representation Theory. The main part describes the implementation of lambda-DRT, as a worked out semantic representation language for the Verbmobil project, which is designed to meet the special requirements of the application. Finally, we discuss future extensions and modications of the formalism

Multiple Discourse Relations on the Sentential Level in Japanese

In the German government (BMBF) funded project Verbmobil, a semantic formalism Language for Underspecified Discourse Representation Structures (LUD) is used which describes several DRSs and allows for underspecification. Dealing with Japanese poses challenging problems. In this paper, a treatment of multiple discourse relation constructions on the sentential level is shown, which are common in Japanese but cause a problem for the formalism,. The problem is to distinguish discourse relations which take the widest scope compared with other scope-taking elements on the one hand and to have them underspecified among each other on the other hand. We also state a semantic constraint on the resolution of multiple discourse relations which seems to prevail over the syntactic c-command constraint.Comment: 6 pages, Postscrip

The Verbmobil semantic formalism (Version 1.3)

This report describes the semantic formalism developed at Saarbrücken University as part of the Verbmobil project. The formalism is based upon DRT with additional functionality to meet the requirements on semantic construction arising from spoken dialogue translation. We define the syntax of the formalism and illustrate the semantic composition process in detail

The role of semantics in spoken dialogue translation systems

In this paper, we consider the role of semantics in the spoken dialogue translation systems. We begin by looking at some of the key properties of an existing spoken dialogue system, namely the sundial system which provides flight and train information over the telephone, and how these properties affect the design methodology and functionality of spoken translation systems. These properties include the effects of speech processing, designing the system to meet the needs of users, and an analysis model which clearly separates the linguistic, conceptual, pragmatic and task levels. In this model many task functionalities are dependent upon, and sometimes realizable by, the semantic and pragmatic analysis components. Central to this approach, is the use of underspecified semantic representations which are further specified as and when required by domain and/or task analysis. This model can be applied in the development of spoken translation systems with two important effects: monolingual semantic and pragmatic analysis can be carried out by processes independent of, but correlated with, the (translation) function of the system; and the main functions of the transfer processes is to further specifying the representations for the target language and to deal with mismatches between source and target language representations. We illustrate this approach with semantic analyses of German utterances required for translation in the verbmobil spoken dialogue translation system

Modelling Users, Intentions, and Structure in Spoken Dialog

We outline how utterances in dialogs can be interpreted using a partial first order logic. We exploit the capability of this logic to talk about the truth status of formulae to define a notion of coherence between utterances and explain how this coherence relation can serve for the construction of AND/OR trees that represent the segmentation of the dialog. In a BDI model we formalize basic assumptions about dialog and cooperative behaviour of participants. These assumptions provide a basis for inferring speech acts from coherence relations between utterances and attitudes of dialog participants. Speech acts prove to be useful for determining dialog segments defined on the notion of completing expectations of dialog participants. Finally, we sketch how explicit segmentation signalled by cue phrases and performatives is covered by our dialog model.Comment: 17 page

Morphology and speech technology

This paper describes a morphological component in a speech recognition architecture for German dealing with the recognition of compounds from their individual constituents. The specification of our morphological model allows for variation in functionality, e.g. the reconstruction of split compounds, of lexicalised, and of non-lexicalised (unknown) compounds.An implementation and evaluation results for split compounds are presented

Dialogue acts in automatic dialogue interpreting

In this paper we demonstrate that for an adequate translation of an utterance spoken in a dialogue the dialogue act it performs has to be determined. We introduce an approach that automatically assigns types of dialogue acts to utterances on the basis of both micro- and macro-structural information. Technically, this assignment is realized by modeling preference rules as weighted defaults in the Description Logic system FLEX. The dialogue-act type of an utterance is determined by qualitatively minimizing the exceptions to these defaults. The results described here have been developed within the VERBMOBIL project, a project concerned with face-to-face dialogue interpreting funded by the German Federal Ministry of Education, Science, Research and Technology (BMBF). We present the rather positive results of a first evaluation of this implementation showing the accuracy of dialogue act assignment

Implementing the syntax of japanese numeral classifiers

While the sortal constraints associated with Japanese numeral classifiers are wellstudied, less attention has been paid to the details of their syntax. We describe an analysis implemented within a broadcoverage HPSG that handles an intricate set of numeral classifier construction types and compositionally relates each to an appropriate semantic representation, using Minimal Recursion Semantics