Learning Phrasal Categories

In this work we learn clusters of contextual annotations for non-terminals in the Penn Treebank. Perhaps the best way to think about this problem is to contrast our work with that of Klein and Manning (2003). That research used treetransformations to create various grammars with different contextual annotations on the non-terminals. These grammars were then used in conjunction with a CKY parser. The authors explored the space of different annotation combinations by hand. Here we try to automate the process -- to learn the "right" combination automatically. Our results are not quite as good as those carefully created by hand but they are close (84.8 vs 85.7).

• Type: Conference
• Year: 2006
• Where: EMNLP
• Authors: William P. Headden III, Eugene Charniak, Mark Johnson
• Keywords: Contextual Annotations, EMNLP 2006, EMNLP 2007, Penn Treebank, Research Used Treetransformations