A Predictive Left-Corner Parser for Tree Adjoining Grammars

Tree Adjoining Grammar (TAG) is a formalism that has become very popular for the description of natural languages. However, the parsers for TAG that have been defined on the basis of the Earley’s algorithm entail important computational costs. In this article, we propose to extend the left corner relation from Context Free Grammar (CFG) to TAG in order to define an efficient left corner parser for TAG that improves the performance of the Earley-like parsers guaranteeing the valid prefix property, due to a remarkable reduction in the number of predictions operations with respect to Earley-like parsing algorithms.