Evaluating a Focus-Based Approach to Anaphora Resolution

We present an approach to anaphora resolution based on a focusing algorithm, and implemented within an existing MUC (Message Understanding Conference) Information Extraction system, allowing quantitative evaluation against a substantial corpus of annotated real-world texts. Extensions to the basic focusing mechanism can be easily tested, resulting in refinements to the mechanism and resolution rules. Results are compared with the results of a simpler heuristic-based approach.

Resolving Anaphors in Embedded Sentences

We propose an algorithm to resolve anaphors, tackling mainly the problem of intrasentential antecedents. We base our methodology on the fact that such antecedents are likely to occur in embedded sentences. Sidner's focusing mechanism is used as the basic algorithm in a more complete approach. The proposed algorithm has been tested and implemented as a part of a conceptual analyser, mainly to process pronouns. Details of an evaluation are given.

An Algorithm to Co-Ordinate Anaphora Resolution and PPS Disambiguation Process

This paper concerns both anaphora resolution and prepositional phrase (PP) attachment that are the most frequent ambiguities in natural language processing. Several methods have been proposed to deal with each phenomenon separately, however none of proposed systems has considered the way of dealing both phenomena. We tackle this issue, proposing an algorithm to co-ordinate the treatment of these two problems efficiently, i.e., the aim is also to exploit at each step all the results that each component can provide.