Universität Bielefeld - Sonderforschungsbereich 360

Situated Reference in Cognitive Systems

Hans Strohner (Ed.)

Preface

Many instructions in natural language are referentially incomplete, vague or ambiguous. For a situated artificial communicator, the solution of reference problems is one of the most urgent tasks. In this research report, a theoretical framework for reference solution is described from the viewpoint of cognitive systems theory. According to this theory, reference is a relation between a conceptual structure in the system and the external situation. This relation is influenced not only bye the characteristics of the referential concept and its coherence with other concepts in the verbal instruction, but also by the communicative situation. Thus, it is crucial to develop a notion of situated reference within a cognitive systems approach to language processing.

Modelling in the cognitive systems approach consistes of empirical as well as formal methods. In this report, empirical aspects are considered. The formal methods will be discussed in following reports of this research project. The cognitive systems approach to situated reference is empirically based on discourse analytic research as well as on experimental methods. I consider the combination of various empirical methods as a fruitful way for obtaining ecologically valid and specific data from the communicative complexity in which referential processes are embedded.

Reference production and comprehension are complex cognitive systems that comprise several components and functions. Three important components are the lexical representation, the working memory and the attentional system. A main function of reference is to provide links between communication and the embedding situation.

The four papers combinded in this report discuss these topics in close relationship to each other:

  1. The first paper discusses the relationship between reference and lexical semantics from a cognitive systems viewpoint. According to this view, reference is combinded with lexical semantics by means of reference concepts. Reference concepts constitute special concepts which emerge from word concepts through elaborations with world knowledge.

  2. Cognitive processing takes place in working memory which is limited in capacity. Therefore, working memory is an important constraint for language processing in general an coherence construction in particular. Since most referential expressions occur in the context of complete utterances, we have to take into accoutn potential coherence problems in analysing referential processing. The discussions of the second contribution to this report include the relationship between linguistic coherence and reference. This study will be published in Rickheit, G. & Habel, C. (Eds.)(1995). Focus and coherence in discourse processing. Berlin: de Gruyter.

  3. How do listeners solve ambiguity problems in referential expressions? One major strategy to handle such problems is the use of additional information sources. As we learn from the third paper, focus is such an information source.

  4. Last but not least, referential processing is embedded in communication. The final study of this report presents some observations of referential communication between partners in a task oriented dialogue.
Though the lexicon, coherence, focus and communication are certainly relevant aspects for processing linguistic reference, research into these topics has only just begun. I hope that this research may serve as a basis for future efforts in investigating reference problems and their solution in natural language communication.

Bielefeld, March 1995
Hans Strohner

Anke Weinberger, 1995-05-09