Many machine translation metrics have been proposed in recent years, such as BLEU (Papineni et al., 2002), NIST (Doddington, 2002), TER (Snover et al., 2006), Meteor (Banerjee and Lavie, 2005) and its extensions, and the MEANT family (Lo and Wu, 2011), amongst others.
evaluating translation, however, is not easy.