Number non-terminals

Lecture Theory of Automata: Lesson 33. The main topics covered in this chapter include: construct the CFG for the language of strings, beginning and ending in same letters; the expressions can be calculated starting from bottom to the top, replacing each nonterminal by the result of calculation;...

18p wangziyi_1307 26-04-2022 15 2   Download

An open problem in dependency parsing is the accurate and efficient treatment of non-projective structures. We propose to attack this problem using chart-parsing algorithms developed for mildly contextsensitive grammar formalisms. In this paper, we provide two key tools for this approach. First, we show how to reduce nonprojective dependency parsing to parsing with Linear Context-Free Rewriting Systems (LCFRS), by presenting a technique for extracting LCFRS from dependency treebanks.

9p bunthai_1 06-05-2013 38 1   Download

Synchronous Tree-Adjoining Grammar (STAG) is a promising formalism for syntaxaware machine translation and simultaneous computation of natural-language syntax and semantics. Current research in both of these areas is actively pursuing its incorporation. However, STAG parsing is known to be NP-hard due to the potential for intertwined correspondences between the linked nonterminal symbols in the elementary structures.

9p hongphan_1 15-04-2013 47 2   Download