The challenge in structured prediction largely stems from the size of the output space.
in NLP, for sequence labeling (e.g., named entity recognition), which is the first building block of our system, a number of different methods have been proposed, namely CRFs (Lafferty et al., 2001), Maximum Margin Markov Network (M 3 N) (Taskar et al., 2003), SVM struct (Tsochantaridis et al., 2004) and SEARN (Daumé III et al., 2009).