Improving Chinese-English PropBank Alignment

Abstract

We describe 2 improvements to Chinese-English PropBank predicate-argument structure alignment. Taking advantage of the recently expanded PropBank English nominal and adjective predicate annotation (Bonial et al., 2014), we performed predicate-argument alignments between both verb and nominal/adjective predicates in Chinese and English. Using our alignment system, this increased the number of aligned predicate-argument structures by 24.5% on the parallel Xinhua News corpus. We also improved the PropBank alignment system using expectation-maximization (EM) techniques. By collecting Chinese-English predicate-to-predicate and argument type-to-argument type alignment probabilities and iteratively improving the alignment output using these probabilities on a large unannotated parallel corpora, we improved the predicate alignment performance by 1 F point when using all automatic SRL and word alignment inputs.