Lexicalized Tree Adjoining Grammar

A Lexicalized Tree Adjoining Grammar is a Tree Adjoining Grammar where each Elementary Tree has at least one Terminal Symbol as a Leaf Node.

• AKA: LTAG.
• Counter-Example(s):
  • a Non-Lexicalized TAG.
• See: Lexicalized .

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References

1997

• (Joshi & Schabes, 1997)
  • “explain how every CFG can be strongly lexicalized by TAG
  • “show that Tree-Adjoining Languages are closed under lexicalization: every TAL has a lexicalized TAG grammar
  • Lexicalization has some useful effects:
    • finite ambiguity: corresponds to our intuition about NL ambiguities,
    • statistical dependencies between words can be captured which can improve parsing accuracy

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