Use of Machine Readable Dictionaries for Word-Sense Disambiguation in SENSEVAL-2

CL Research's word-sense disambiguation (WSD) system is part of the DIMAP dictionary software, designed to use any full dictionary as the basis for unsupervised disambiguation. Official SENSEV AL-2 results were generated using WordNet, and separately using the New Oxford Dictionary of English (NODE). The disambiguation functionality exploits whatever information is made available by the lexical database. Special routines examined multiword units and contextual clues (both collocations, definition and example content words, and subject matter analyses); syntactic constraints have not yet been employed. The official coarsegrained precision was 0.367 for the lexical sample task and 0.460 for the all-words task (these are actually recall, with actual precision of 0.390 and 0.506 for the two tasks). NODE definitions were automatically mapped into WordNet, with precision of0.405 and 0.418 on 75% and 70% mapping for the lexical sample and all-words tasks, respectively, comparable to WordNet. Bug fixes and implementation of incomplete routines have increased the precision for the lexical sample to 0.429 (with many improvements still likely).