Speed and accuracy in shallow and deep stochastic parsing

This paper reports some experiments that compare the accuracy and performance of two stochastic parsing systems. The currently popular Collins parser is a shallow parser whose output contains more detailed semantically-relevant information than other such parsers. The XLE parser is a deep-parsing system that couples a Lexical Functional Grammar to a log-linear disambiguation component and provides much richer representations theory. We measured the accuracy of both systems against a gold standard of the PARC 700 dependency bank, and also measured their processing times. We found the deep-parsing system to be more accurate than the Collins parser with only a slight reduction in parsing speed.(1).