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A Variant of Earley Parsing

Mark-Jan Nederhof·Giorgio Satta
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Abstract

The Earley algorithm is a widely used parsing method in natural language processing applications. We introduce a variant of Earley parsing that is based on a ``delayed'' recognition of constituents. This allows us to start the recognition of a constituent only in cases in which all of its subconstituents have been found within the input string. This is particularly advantageous in several cases in which partial analysis of a constituent cannot be completed and in general in all cases of productions sharing some suffix of their right-hand sides (even for different left-hand side nonterminals). Although the two algorithms result in the same asymptotic time and space complexity, from a practical perspective our algorithm improves the time and space requirements of the original method, as shown by reported experimental results.

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Mark-Jan Nederhof, Giorgio Satta. 1998-08-31. A Variant of Earley Parsing. https://arxiv.org/abs/cmp-lg/9808017

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