In addition, conclusions from different reports can be contradictory. For example, most work observes that stochastic gradient descent (SGD) gives best performance on NER task (Chiu and Nichols, 2016; Lample et al., 2016; <cite>Ma and Hovy, 2016</cite>) , while Reimers and Gurevych (2017b) report that SGD is the worst optimizer on the same datasets.