Parsing Inside-Out

Joshua Goodman

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arXiv · cmp-lg/9805007

Parsing Inside-Out

Joshua Goodman

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Abstract

The inside-outside probabilities are typically used for reestimating Probabilistic Context Free Grammars (PCFGs), just as the forward-backward probabilities are typically used for reestimating HMMs. I show several novel uses, including improving parser accuracy by matching parsing algorithms to evaluation criteria; speeding up DOP parsing by 500 times; and 30 times faster PCFG thresholding at a given accuracy level. I also give an elegant, state-of-the-art grammar formalism, which can be used to compute inside-outside probabilities; and a parser description formalism, which makes it easy to derive inside-outside formulas and many others.

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Joshua Goodman. 1998-05-19. Parsing Inside-Out. https://arxiv.org/abs/cmp-lg/9805007

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