Växjö University Joakim Nivre Växjö University

2 Who? Växjö University (800) School of Mathematics and Systems Engineering (120) Computer Science division (30) Language Technology group (5):  Models and Algorithms in Language Technology (MALT)

3 Växjö University Why? Main focus of research:  Robust and efficient algorithms for natural language processing  Machine learning to improve accuracy Need for treebanks:  Training and validation in machine learning  Evaluation of accuracy No large treebank available for Swedish!

4 Växjö University What? Projects  Swedish Treebank: Pilot project funded by The Bank of Sweden Tercentennary Foundation (RJ) Symposium in Växjö, November 2002 Project proposal to RJ, March 2003  Stochastic Dependency Grammars: Theoretical properties of dependency grammars Robust and efficient parsing algorithms Machine learning to improve parsing accuracy

5 Växjö University What? Corpora:  SynTag converted to dependency trees: 100 k words, manually annotated (Järborg 1986) Automatic conversion to dependency trees Tools:  Trainable part-of-speech tagger Efficient in training and tagging Suffix model for unknown words  Dependency parser (under development) Linear time projective dependency parsing Trainable through external parse table