Institut

Studium

Forschung


 

University of Stuttgart
Institute for Computational Linguistics
The SFB340/B9 Project


Project-title:

Construction of Semantic Representations for a Large Fragmentof German.

Projectleader:

Prof. Hans Kamp, Prof. Rohrer

Project-staff:


  • Dr. Kurt Eberle (until 1996)
  • Peter Krause (from 1997)
  • Michael Seizmair (from 1997)
  • Carl Vogel PhD (until 1996)

Description:

The purpose of this project is to design and implement an algorithmfor the construction of semantic representations of sentences andtexts for a fragment of German with substantial coverage. As inputthe algorithm uses analyses delivered by an HPSG parser developed in asister project within the SFB (but located at T�bingen University);as output it produces underspecified Discourse RepresentationStructures. The projected output representations are underspecifiedin more than one sense; they incorporate devices familiar from UDRT(seeReyle93a,Reyle94,Reyle95b) for theunderspecification of such structural aspects of meaning as scoperelations or the collective-distributive distinction, but they mayalso contain partial meaning specifications of other kinds, such as,say, an ambiguous lexical predicate instead of a particulardisambiguation of it (seeEberle95b). Partiality of the secondkind is unavoidable in such an enterprise,

  1. because disambiguationhas to proceed on the basis of a preliminary, underspecified semanticrepresentation;
  2. because the lexicon required by a high qualitysemantic representation system will become available only graduallyand in the meantime the system will have to make do with certain "stopgap solutions" lest it break down at every turn. Thus,underspecification techniques in semantics can contribute to theefficacy of robust parsing methods (seeVog94) in general.
Jointly with a construction algorithm for underspecifiedrepresentation the project endeavours to develop strategies forremoving elements of underspecification from representations as theyare being constructed, in particular strategies which involveinferencing on those underspecified representations. In this no lessthan in the design of a mode of underspecified representation theproject cooperates with other SFB projects, in particular A5, B3, C2and C3. Special attention is being given in this connection to thesemantics and logic of space, time and motion (seeEberle91c,Eberle92a,Eberle95a). As HPSG bills itself as an"information-based theory of syntax and semantics," researchers withinB9 are also concerned with direct integration of the expressiveprimitives required by the ultimate semantic analyses into HPSGfeature descriptions in a way that maintains descriptive adequacy withminimum processing complexity costs (seePop91a,Vog92).

Implementation:

iXi system ("Integrated Computational Semantics Implementation")



IMS Stuttgart, Fri Apr 16 21:17:32 1999 (www@ims.uni-stuttgart.de)