Introduction to this Special Issue

This issue of Natural Language Engineering journal reports on recent achievements in the domain of HPSG -based parsing. Research groups at Saarbrücken, CSLI Stanford and the University of Tokyo have worked on grammar development and processing systems that allow the use of HPSG -based processing in practical application contexts. Much of the research reported here has been collaborative, and all of the work shares a commitment to producing comparable results on wide-coverage grammars with substantial test suites. The focus of this special issue is deliberately narrow, to allow detailed technical reports on the results obtained among the collaborating groups. Thus, the volume cannot aim at providing a complete survey on the current state of the field. This introduction summarizes the research background for the work reported in the issue, and puts the major new approaches and results into perspective. Relationships to similar efforts pursued elsewhere are included, along with a brief summary of the research and development efforts reflected in the volume, the joint reference grammar, and the common sets of reference data.