|
| Speaker: | ||
| Department of Computer Science | University of Toronto | |
| Date: | 28th April 1998 | |
| Time: | 11:30am | |
| Place: | Seminar Room 357, Department of Computing, Building E6A, Macquarie University |
Abstract
Plesionyms, or near-synonyms, are words, that, within or across languages, are almost synonyms---but not quite. Some examples: "forest", "woods", German "Wald"; "fib", "lie", "misrepresentation". Near-synonyms may differ in one or more of the following: connotation, emphasis on subcomponents, implicature, denotation, speaker's expressed attitude, register, and structural or selectional requirements. In all but the last two of these, the distinction between two near-synonyms is at least in part conceptual.
It is necessary to represent lexical meaning finely enough that distinctions between near-synonyms can adequately be taken into account in such tasks as lexical choice in machine translation and mono- and multilingual text generation. This is the basis for two alternatives to conventional models of lexical knowledge: a prototype-theory approach and a Saussurean approach. In this paper, I will discuss these approaches, showing that the former is troublesome, while the latter is more promising; but ultimately, elements of both are required. I will discuss the consequences of this for computational models of lexical knowledge.Biography
Graeme Hirst received a PhD in Computer Science from Brown University in 1983, and has worked at the University of Toronto ever since.
Professor Hirst's research has covered a broad but integrated range of topics in computational linguistics, natural language understanding, and related areas of cognitive science. These include the resolution of ambiguity in language understanding; psychological reality in natural language systems; the preservation of author's style in machine translation; recovering from misunderstanding and non-understanding in human-computer communication; and linguistic constraints on knowledge-representation systems. His present research includes the problem of near-synonymy in lexical choice in language generation; computer assistance for collaborative writing; and applications of lexical chaining as an indicator of semantic distance in texts. A recent spinoff of this research is an intelligent spelling checker. Professor Hirst is also a member of the Waterloo-Toronto HealthDoc project, which is building intelligent systems for the creation and customization of health-care documents. Professor Hirst was the founding editor of Canadian Artificial Intelligence, and is on the editorial boards of Machine Translation and Computational Linguistics, having been book review editor of the latter for more than a decade. He has written or co-authored over 60 research papers, and is the author of two monographs: Anaphora in Natural Language Understanding (Springer-Verlag, 1981) and Semantic Interpretation and the Resolution of Ambiguity (Cambridge University Press, 1987). He is the recipient of two awards for excellence in teaching, and a best-paper award at the AAAI-84 conference. He has supervised more than 25 theses and dissertations, two of which have been published as books.Enquiries: sals@mri.mq.edu.au
| Last modified: February, 1998 |