We implement three baseline models for comparison: Noun WordNet Semantic Text Exchange Model (NWN-STEM), General WordNet Semantic Text Exchange Model (GWN-STEM), and Word2Vec Semantic Text Exchange Model (W2V-STEM). 
 Question: What are the baseline models mentioned in the paper?
Noun WordNet Semantic Text Exchange Model (NWN-STEM) General WordNet Semantic Text Exchange Model (GWN-STEM) Word2Vec Semantic Text Exchange Model (W2V-STEM)