Lynne J. Cahill

A Reference Architecture for Natural Language Generation Systems

We present the RAGS (Reference Architecture for Generation Systems) framework: a specification of an abstract Natural Language Generation (NLG) system architecture to support sharing, re-use, comparison and evaluation of NLG technologies. We argue that the evidence from a survey of actual NLG systems calls for a different emphasis in a reference proposal from that seen in similar initiatives in information extraction and multimedia interfaces. We introduce the framework itself, in particular the two-level data model that allows us to support the complex data requirements of NLG systems in a flexible and coherent fashion, and describe our efforts to validate the framework through a range of implementations.

German noun inflection.

This is the second of a series of three papers that, taken together, will give an essentially complete account of inflection in standard German. In this paper we present that part of the account that covers nouns, one that captures all the regularities, subregularities and irregularities that are involved, but with a focus on the subregularities. Inflected forms are defined in terms of their syllable structure, as proposed in Cahill (1990a, b, 1993). The analysis is formulated as a DATR theory – a set of lexical axioms – from which all the relevant facts follow as theorems. DATR is a widely used formal lexical knowledge representation language developed for use in computational linguistics.

The inflectional phonology of German adjectives, determiners, and pronouns

This is the first of a series of papers that, taken together, will give an essentially complete account of inflection in standard German. In this paper we present that part of the account that covers adjectives, determiners, and third-person pronouns, one that captures all the regularities, subregularities, and irregularities that are involved. The forms are defined in terms of their syllable structure, as proposed in Cahill (1990a, 1990b, 1993). The morphological treatment is based on ideas originally set out by Zwicky (1985). The analysis is formulated as a DATR theory - a set of lexical axioms - from which all the relevant facts follow as theorems. DATR is a widely used formal lexical-knowledge-representation language developed for use in computational linguistics

A Reference Architecture for Generation Systems

We present the RAGS (Reference Architecture for Generation Systems) framework, a specification of an abstract Natural Language Generation (NLG) system architecture to support sharing, re-use, comparison and evaluation of NLG technologies. We argue that the evidence from a survey of actual NLG systems calls for a different emphasis in a reference proposal from that seen in similar initiatives in information extraction and multimedia interfaces. We introduce the framework itself, in particular the two-level data model that allows us to support the complex data requirements of NLG systems in a flexible and coherent fashion, and describe our efforts to validate the framework through a range of implementations.

From RAGS to RICHES: Exploiting the Potential of a Flexible Generation Architecture

The RAGS proposals for generic specification of NLG systems includes a detailed account of data representation, but only an outline view of processing aspects. In this paper we introduce a modular processing architecture with a concrete implementation which aims to meet the RAGS goals of transparency and reusability. We illustrate the model with the RICHES system -- a generation system built from simple linguistically-motivated modules.

Morphonology in the lexicon

In this paper we present a means of defining morphonological phenomena in an inheritance based lexicon. We make use of the theory behind the formal language MOLUSC, in which morphological alternations were defined as mappings between sequences of tree-structured syllables. We discuss how the alternations can be defined in the inheritance-based lexical representation language DATR, and how the phonological aspects can be built upon to bring it closer to an integrated lexicon with representations which can be used by both the morphology and phonology of a language.

Syllable-based morphology

This paper presents a language for the description of morphological alternations which is based on syllable structure. The justification for such an approach is discussed with reference to examples from a variety of languages and the approach is compared to Koskenniemis two-level account of morphonology.

A Representation for Complex and Evolving Data Dependencies in Generation

This paper introduces an approach to representing the kinds of information that components in a natural language generation (NLG) system will need to communicate to one another. This information may be partial, may involve more than one level of analysis and may need to include information about the history of a derivation. We present a general representation scheme capable of handling these cases. In addition, we make a proposal for organising intermodule communication in an NLG system by having a central server for this information. We have validated the approach by a reanalysis of an existing NLG system and through a full implementation of a runnable specification.

Natural language processing in clime, a multilingual legal advisory system†

This paper describes CLIME, a web-based legal advisory system with a multilingual natural language interface. CLIME is a ‘proof-of-concept’ system which answers queries relating to ship-building and ship-operating regulations. Its core knowledge source is a set of such regulations encoded as a conceptual domain model and a set of formalised legal inference rules. The system supports retrieval of regulations via the conceptual model, and assessment of the legality of a situation or activity on a ship according to the legal inference rules. The focus of this paper is on the natural language aspects of the system, which help the user to construct semantically complex queries using WYSIWYM technology, allow the system to produce extended and cohesive responses and explanations, and support the whole interaction through a hybrid synchronous/asynchronous dialogue structure. Multilinguality (English and French) is viewed simply as interface localisation: the core representations are language-neutral, and the system can present extended or local interactions in either language at any time. The development of CLIME featured a high degree of client involvement, and the specification, implementation and evaluation of natural language components in this context are also discussed.

POETIC: A system for gathering and disseminating traffic information

The Portable Extendable Traffic Information Collator (POETIC) is a software system that extracts traffic information from police incident logs and initiates (simulated) broadcasts of traffic bulletins to motorists when appropriate. The initial prototype system (TIC) was limited to the practices and requirements of a single police force. In this paper, the authors describe the second stage prototype system ( POETIC), in which the architecture and data representations have been generalized to make the system tailorable to many different police force domains.