Some of these studies have shown that simple linear classifiers with uni-gram and n-gram features are effective for this task (Somasundaran and Wiebe, 2010;Hasan and Ng, 2013;Mohammad et al., 2016).
in our setting, since we try to predict the stance between all pairs of claims on an argument path, rather than simply claims that are directed towards the thesis or the parent claim, we find that the models with a hierarchical representation of the argument path, i.e.