22. The apparatus for use in a natural language processing system of claim 16 , further comprising a syntactical parsing apparatus that resolves structural ambiguities of said text documents whereby additional contextual features are extracted.
16. An apparatus for use in a natural language processing system for resolving natural language ambiguities within text documents, comprising: a trainer that trains probabilistic classifiers from annotated training data containing a sense tag for each polysemous word; a part-of-speech processor that processes said text documents into tokens and determines their part-of-speech tags; a classifier module that computes a measure of confidence using said probabilistic classifiers for each known sense of said tokens defined within a semantic lexicon based on contextual features and assigns a default sense for tokens absent from said semantic lexicon based on their part-of-speech tags; a word sense disambiguator that determines assignment of word senses for each said token in said sentence such that the combined probability across said sentence is maximized; and a context integrator that integrates additional contextual features as generated by one or more of the following natural language processing apparatuses into said probabilistic classifiers whereby said measure of confidence is improved: using a chunking apparatus that identifies multi-word phrases and the associated measure of confidence for each phrase; using a named-entity recognition apparatus that identifies named entities and the associated measure of confidence for each entity; using a syntactic parsing apparatus that constructs sentential parse trees and the associated measure of confidence for each tree; using an anaphora resolution apparatus that identifies anaphor references and the associated measure of confidence for each reference; using a discourse categorization apparatus that determines document categories and the associated measure of confidence for each category; using a discourse structure analysis apparatus that determines discourse structures and the associated measure of confidence for each structure.