Another Facet of LIG Parsing
Pierre Boullier (INRIA-Rocquencourt, Le Chesnay Cedex, France)

TL;DR
This paper introduces a new parsing algorithm for linear indexed grammars that constructs a context-free grammar representing valid derivations for a given string, with potential practical efficiency improvements.
Contribution
The paper presents a novel parsing method for LIGs that constructs a context-free grammar of derivations, with an ${ m O}(n^6)$ worst-case complexity and improved average-case performance.
Findings
Constructs a context-free grammar of derivations for LIGs
Parsing can be done in linear time relative to parse tree size
Average case performance is significantly better than worst-case
Abstract
In this paper we present a new parsing algorithm for linear indexed grammars (LIGs) in the same spirit as the one described in (Vijay-Shanker and Weir, 1993) for tree adjoining grammars. For a LIG and an input string of length , we build a non ambiguous context-free grammar whose sentences are all (and exclusively) valid derivation sequences in which lead to . We show that this grammar can be built in time and that individual parses can be extracted in linear time with the size of the extracted parse tree. Though this upper bound does not improve over previous results, the average case behaves much better. Moreover, practical parsing times can be decreased by some statically performed computations.
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsNatural Language Processing Techniques · Algorithms and Data Compression · semigroups and automata theory
