While some higher-level linguistic properties of the target language have been incorporated through selective sharing, so far no features specific to the target language have been employed. Cohen et al. (2011) and <cite>Naseem et al. (2012)</cite> have shown that using expectation-maximization (EM) to this end can in some cases bring substantial accuracy gains. However, as discussed in §5.2, standard self-training is not optimal for target language adaptation.