Introduction to Natural Language Processing (600.465)Statistical Parsing

Language Model vs. Parsing Model

Once again, Lexicalization

Lexicalized Tree Example

Using POS Tags

Conditioning

Independence Assumptions

The Decomposition

Example Decomposition

More Conditioning: Distance

More Conditioning: Complement/Adjunct

More Conditioning: Subcategorization

Inserting Subcategorization

Smoothing

The Parsing Algorithm for a Lexicalized PCFG

Results