We use Waseem and Hovy BIBREF5, Davidson et al. BIBREF9, and Waseem et al. BIBREF10 as baselines and compare the results with our different fine-tuning strategies using pre-trained BERTbase model.  
 Question: What existing approaches do they compare to?
Waseem and Hovy BIBREF5, Davidson et al. BIBREF9, and Waseem et al. BIBREF10