Irrespective of the existence of the dictionary features, the joint model SegTagDep largely increases the POS tagging and dependency parsing accuracies (by 0.56-0.63% and 2.34-2.44%); the improvements in parsing accuracies are still significant even compared with SegTag+Dep' (the pipeline model with the look-ahead features).
when the external dictionaries are not used ("wo/dict"), no substantial improvements for segmentation accuracies were observed.