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Acquisition of the Lexicon

  Any attempt to represent and disambiguate word senses depends heavily on the representation of lexical semantic information. Many of the early NLP systems relied on hand-coding of the lexicon, but this was quickly realised to be problematic for the development of large-scale systems. Research turned to development of automated techniques for encoding of the lexicon. The initial attempts in this area were made by basing lexica on electronic versions of dictionaries, Machine Readable Dictionaries (MRDs). However, the need for frequency and co-occurrence information as argued for by mcroy:92 and copestake_briscoe:95 points to the need to augment lexica with information which can be derived only through corpus analysis. In this section, I will review several attempts to extract lexica from each of these sources.