Natural Language Generation (201-2454101)
Notes Week 3 - Spring 1997 - Michael Elhadad
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Introduction to FUF

See also:

Role of grammar formalism

Meta-language to describe: Why need a formal language for grammar: Criteria on choice of a formalism: Design decisions: Definition of feature structures: Why feature structures for encoding of linguistic knowledge? Formal definition:

Place of syntactic realization component in a generator

Standard Architecture: content planning - lexical choice - syntactic realization. Form of input received: Provides: Example:
"She eats a pie"

((cat clause)
 (process ((type material)
           (lex "eat")))
 (participants ((agent ((cat personal-pronoun)
                        (gender feminine)))
                (affected ((cat np)
                           (lex "pie")
                           (definite no))))))

Role of a syntactic realization component

  1. Map thematic structure onto syntactic roles
  2. Control syntactic paraphrasing and alternations
  3. Prevent over-generation
  4. Provide defaults for syntactic features
  5. Propagate agreement features (down to morphology)
  6. Select closed-class words
  7. Provide linear-precedence constraints among syntactic constituents
  8. Inflect open-class words
  9. Linearize syntactic tree into a string of inflected words
  10. Perform syntactic inference

Evaluation Criteria for Syntactic Realization Components

Desired features:

Last modified March 19th, 1997
Michael Elhadad