We argue in this article that many common adverbial phrases generally taken to signal a discourse relation between syntactically connected units within discourse structure instead work anaphor- ically to contribute relational meaning, with only indirect dependence on discourse structure. This allows a simpler discourse structure to provide scaffolding for compositional semantics and reveals multiple ways in which the relational meaning conveyed by adverbial connectives can interact with that associated with discourse structure. We conclude by sketching out a lexicalized grammar for (...) discourse that facilitates discourse interpretation as a product of compositional rules, anaphor resolution, and inference. (shrink)
The questions of how human beings produce and comprehend language continue to engage a variety of researchers and scholars, and it is becoming increasingly clear that only interdisciplinary approaches will yield productive answers. This complex issue of discourse processing is the subject of this volume, and the contributors address it from the varying perspectives of cognitive psychology linguistics, and computer science. The chapters provide a fascinating overview of emerging theories in the new discipline of cognitive science. A useful introductory chapter (...) by the editors explains the relationships of chapters to one another and outlines the long-term implications of the work they report. (shrink)
This paper surveys work on applying the insights of lexicalized grammars to low‐level discourse, to show the value of positing an autonomous grammar for low‐level discourse in which words (or idiomatic phrases) are associated with discourse‐level predicate–argument structures or modification structures that convey their syntactic‐semantic meaning and scope. It starts by describing a lexicalized Tree Adjoining Grammar for discourse (D‐LTAG). It then reviews an initial experiment in parsing text automatically, using both a lexicalized TAG and D‐LTAG, and then touches upon (...) issues involved in how lexico‐syntactic elements contribute to discourse semantics. The paper concludes with a brief description of the Penn Discourse TreeBank, a resource being developed for the study of discourse structure and semantics. (shrink)
In this paper, we claim that the disambiguation ofreferring expressions in discourse can be formulated in terms automatedreasoners can address. Specifically, we show that consistency,informativity and minimality are criteria which (i) can be implementedusing automated reasoning tools and (ii) can be used to disambiguatenoun-noun compounds, metonymy and definite descriptions.
In his recent article “Verbs, Time and Modality,” M. J. Steedman (1977) proposes a recursive scheme for identifying the aspectual character of a proposition. The purpose of this squib is to point out some faults and gaps in that account that may suggest some interesting directions for future research.
We present an implementation of a discourse parsing system for alexicalized Tree-Adjoining Grammar for discourse, specifying the integrationof sentence and discourse level processing. Our system is based on theassumption that the compositional aspects of semantics at thediscourse level parallel those at the sentence level. This coupling isachieved by factoring away inferential semantics and anaphoric features ofdiscourse connectives. Computationally, this parallelism is achievedbecause both the sentence and discourse grammar are LTAG-based and the sameparser works at both levels. The approach to an (...) LTAG for discourse has beendeveloped by Webber and colleagues in some recent papers. Our system takes a discourseas input, parses the sentences individually, extracts the basic discourseconstituent units from the sentence derivations, and reparses the discoursewith reference to the discourse grammar while using the same parser usedat the sentence level. (shrink)