An Investigation into the Use of Argument Structure and Lexical Mapping Theory for Machine Translation

Lexical Functional Grammar (LFG) has been quite widely used as the linguistic backbone for recent Machine Translation (MT) systems. The relative order-free functional structure (fstructure) in LFG is believed to provide a suitable medium for performing source-to-target language transfer in a transfer-based MT system. However, the linguistic information captured by traditional f-structure is syntax-based, which makes it relatively language-dependent and thus inadequate to handle the mapping between different languages. Problems are found in the lexical selection and in the transfer from some English passive sentences to Chinese. The recent development of the relatively language-independent argument structure (a-structure) and the lexical mapping theory in the LFG formalism seems to provide a solution to these problems. This paper shows how this can be done and evaluates the effectiveness of the use of a-structures for MT