We propose a format of a binary phrase structure grammar with composite labels.
The grammar adopts binary rules so that the dependency between two sub-trees can
be represented in the label of the tree. The label of a tree is composed of two
attributes, each of which is extracted from each sub-tree, so that it can represent the
compositional information of the tree. The composite label is generated from partof-
speech tags using an automatic labeling algorithm. Since the proposed rule
description scheme is binary and uses only part-of-speech information, it can
readily be used in dependency grammar and be applied to other languages as well.
In the best-1 context-free cross validation on 31,080 tree-tagged corpus, the
labeled precision is 79.30%, which outperforms phrase structure grammar and
dependency grammar by 5% and by 4%, respectively. It shows that the proposed
rule description scheme is effective for parsing Korean.