Follow the principle suggested in the multi-view active learning work (Muslea et al., 2000(Muslea et al., , 2002Zhou, 2008, 2010) that querying labels for contention points (instances on which different views predict different labels) can lead to superior information gain than querying uncertain points, we identify the non-redundant contention points from the two domains for label acquisition.
there are three cases: (1) If only one of the instances is a contention point, we query its label with probability P c (Eq (1)) when the instance is from the target domain, and query its label with probability 1 − P c when the instance is from the source domain.