LTG vs. ITG Coverage of Cross-Lingual Verb Frame Alternations
Karteek Addanki, Chi-kiu Lo, Markus Saers, Dekai Wu · 2012
We show in an empirical study that not only did all cross-lingual alternations of verb frames across Chinese-English translations fall within the reordering capacity of Inversion Transduction Grammars, but more surprisingly, about 97% of the alternations were expressible by the far more restrictive Linear Transduction Grammars. Also, about 71% of the cross-lingual verb frame alternations turn out to be monotonic even for diverse language pairs such as Chinese-English. We also observe that a source verb frame alternation pattern translates into a small subset of the possible target verb frame alternation patterns, based on the construction of the source sentence and the frame set definitions. As a part of our evaluation, we also present a novel linear time algorithm to determine whether a particular syntactic alignment falls within the expressiveness of Linear Transduction Grammars. To our knowledge, this is the first study that attempts to analyze the cross-lingual alternation behavior of semantic frames and the extent of their coverage under syntax-based machine translation formalisms.