However, Sporleder and Lascarides (2008) show that models trained on explicitly marked examples generalize poorly to implicit relation identification. They argued that explicit and implicit examples may be linguistically dissimilar, as writers tend to avoid discourse connectives if the discourse relation could be inferred from context (Grice, 1975) . Similar observations are made by <cite>Rutherford and Xue (2015)</cite> , who attempt to add automatically-labeled instances to improve supervised classification of implicit discourse relations. In this paper, we approach this problem from the perspective of domain adaptation.