Abstract not found

Contents 1. Introduction : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 3 2. The Problem of Anaphoric Linking in Context : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 4 3. Basic Ideas of Discourse Representation : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 5 4. Discourse Representation Structures : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 14 5. The Static and Dynamic Meaning of Representation Structures : : : : : : : : : : : : : : : : : : : : 17 6. Sequential Composition of Representation Structures : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 21 7. Strategies for Merging Representation Structures : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 27 8. Disjoint Mer

Abstract not found

In this paper, we offer a novel analysis of presuppositions, paving particular attention to the interaction between the knowledge resources that are required to interpret them. The analysis has two main features. First, we capture an analogy between presuppositions, anaphora and scope ambiguity (cf. van der Sandt 1992), by utilizing semantic underspecification (c £ Reyle 1993). Second, resolving this underspccification requires reasoning about how the presupposition is rhetorically connected to the discourse context. This has several consequences. First, since pragmatic information plays a role in computing the rhetorical relation, it also constrains the interpretation of presuppositions. Our account therefore provides a formal framework for analysing problematic data, which require pragmatic reasoning. Second, binding presuppositions to the context via rhetorical links replaces accommodating them, in the sense of adding them to the context (cf. Lewis 1979). The treatment of presupposition is thus generalized and integrated into the discourse update procedure. We formalize this approach in SDKT (Asher 1993; Lascarides & Asher 1993), and demonstrate that it provides a rich framework for interpreting presuppositions, where semantic and pragmatic constraints arc integrated.

This paper presents empirical results comparing spoken and keyboard communication. It is shown that speakers attempt to achieve more detailed goals in giving instructions than do users of keyboards. One specific kind of fine-grained communicative act, a request that the hearer identify the referent of a noun phrase, is shown to dominate spoken instruction-giving discourse, but is nearly absent from keyboard discourse. Most important, these requests are only achieved "indirectly". - through utterances whose surface forms do not explicitly convey the speakers' intent. A plan-based theory of communication is shown to uncover the speakers' intentions underlying many cases of indirect identification requests found in the corpus, once an action for referent identification has been posited. In so doing, the theory demonstrates how intent (or plan) recognition can be applied in reasoning about the use of a description. As a consequence of this approach, it is shown that the conditions on the planning of successful identification requests account for Searle's conditions on the act of referring. It is concluded that intent recognition will need to be a central focus for pragmatics/discourse components of future speech understanding systems, and that computational linguistics needs to develop formalisms for reasoning about speakers' use of descriptions

Anchoring is the process of creating and maintaining the correspondence between symbols and percepts that refer to the same physical objects. Although this process must necessarily be present in any symbolic reasoning system embedded in a physical environment (e.g., an autonomous robot), the systematic study of anchoring as a clearly separated problem is just in its initial phase. In this paper we focus on the use of symbols in actions and plans and the consequences this has for anchoring. In particular we introduce action properties and partial matching of objects descriptions. We also consider the use of indefinite references in the context of action. The use of our formalism is exemplified in a mobile robotic domain. 1

The use of logic for knowledge representation and reasoning systems is controversial. There are, indeed, several ways that standard First Order Predicate Logic is inappropriate for modelling natural language understanding and commonsense reasoning. However, a more appropriate logic can be designed. This chapter presents several aspects of such a logic.

In this paper, we present the results of a corpus analysis, and a model of anaphora resolution in spontaneous spoken dialogues in the form of an algorithm. The main finding of our corpus analysis is that less than half the pronouns and demonstratives have NP antecedents in the preceding text. 22% have sentential antecedents and the remainder have no identifiable linguistic antecedents. As part of the corpus analysis we present the results of interannotator agreement tests. These were carried out for marking anaphor types and their antecedents, and for segmenting the dialogues into dialogue acts. The results of the inter-annotator agreement tests indicate that our classification method is reliable and that the annotated dialogues can be used as a standard against which to measure the performance of the resolution algorithm. The algorithm, based on Strube (1998), is capable of classifying pronouns and demonstratives, and co-indexing anaphors with NP and sentential antecedent...

This book deals with the semantics of natural language expressions that are commonly taken to refer to individuals: pronouns, definite descriptions and proper names. It claims, contrary to previous theorizing, that they all have a common syntax and semantics, roughly that which is currently associated by philosophers and linguists with definite descriptions as construed in the tradition of Frege. As well as advancing this proposal, I hope to achieve at least one other aim, that of urging semanticists dealing with pronoun interpretation, in particular donkey anaphora, to consider a wider range of theories at all times than is sometimes done at present. I am thinking particularly of the gulf that seems to have emerged between those who practice some version of dynamic semantics (including DRT) and those who eschew this approach and rely on some version of the E-type analysis for donkey anaphora (if they consider this phenomenon at all). In my opinion there is too little work directly comparing the claims of these two schools (for that is what they amount to) and testing them against the data in the way that any two rival theories might be tested. (Irene Heim’s 1990 article in Linguistics and Philosophy does this, and

We argue that model generation programs, i.e., deduction systems that automatically compute the models satisfying a given finite set of formulas, can provide a procedural interpretation for semantic theories of natural language. We illustrate this claim by describing how singular definite descriptions can be interpreted using the higher-order model generator KIMBA.