... common to statistical machinetranslation (SMT) systems, many of the earlier models particularly child re-ordering models fail to account for human translation behavior.Galley et al. (2004) ... parsing and thus is notdiscussed here. Estimating P r(f |π) is the task ofsyntax-based translation models (SBTM).Given a rule set R, our SBTM makes thecommon assumption that left-most compositionsof ... denote general probability distributions with Pr(·)and use p(·) for probabilities assigned by our models. 964ORNP(x0:NP, x1:VP) x1, !, x0VP(x0:VBP, x1:NP) x0 , x1S(x0:NP, x1:VP, x2:.)...