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Syntactic & Semantic Fundamentals of NLP

Lecture 4

Probabilistic Context-Free Grammars

Krishnendu Ghosh

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Syntax

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Syntax

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Syntax

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Syntax

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Syntax

Motivation for probabilistic grammars

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Estimating rule probabilities from corpora

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Treebanks and annotated corpora (e.g., Penn Treebank)

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Demo: Parse scoring using PCFGs

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