Next, we find that our multi-task model also has low match-with-input scores (2% exact match, 9% BLEU, 38% ROUGE), similar to the behavior of the ground-truth references.
dRESS-LS (and pointer baseline) model is generating output sentences which are substantially closer to the input and hence is not making enough changes (14% exact match, 43% BLEU, 68% ROUGE) as compared to the references (which explains their higher adequacy but lower simplicity scores).