Natural Language Processing (Almost) from Scratch

6.5 Parsing

1. How did parse-tree information help the SRL network?
   Charniak parse levels were fed as IOBES segment tags in extra lookup tables: level 0 (leaf phrases) added almost 1.5 F1, further levels less, up to 76.06, close to the 77.92 benchmark that used six parse trees. A network predicting level-0 segments (PT0) worked as well as the parser and better than chunk tags.
   • Collobert et al., 2011, Natural Language Processing (Almost) from Scratch (Journal of Machine Learning Research), §6.5, pp. 2521–2524