Question: what were the baselines?
Answer: 2008 Punyakanok et al. 
2009 Zhao et al. + ME 
2008 Toutanova et al. 
2010 Bjorkelund et al.  
2015 FitzGerald et al. 
2015 Zhou and Xu 
2016 Roth and Lapata 
2017 He et al. 
2017 Marcheggiani et al.
2017 Marcheggiani and Titov 
2018 Tan et al. 
2018 He et al. 
2018 Strubell et al. 
2018 Cai et al. 
2018 He et al. 
2018 Li et al.