Morphology and Finite-State Transducers

• What is morphology?
  • The internal structure of words: words are composed of one or more morphemes
  • The accompanying semantics: building up the meanings of words from the meaings of morphemes
• Why is morphological analysis useful in CL?
  • To indicate when two different words have the same root; useful in information retrieval and other applications for stemming and term expansion
  • To analyze the semantics of morphologically complex words, in any application that requires sophisticated natural language understanding or generation
• Finite-State Transducers (FSTs)
  • An FST is a finite-state machine with two "tapes": one for input and one for output
  • Why use FSTs for morphological analysis?
  • An example

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