Syntax and Parsing

• The syntax of a sentence really does matter.
• John killed Bob. is different from Bob killed John.
• The syntax of a sentence is typically represented by a tree. (You can do this with brackets).
• (S(NP(NP The syntax) (PP of (NP a sentence))) (VP (VG is typically represented) (PP by (NP a tree)))).
• Generating that tree from the surface form is called parsing.
• Chart parsers are typically used.
• People parse left to right with little backtracking.
• Cascaded FSAs are also used.
• Language is generally considered to be context free.
• Evaluate by comparison to a gold standard (e.g. wall street journal corpus in the penn tree bank).
• Some parsers generate both syntactic and semantic representations.