NLP Applications Based on Weighted Multi-Tape Automata

This article describes two practical applications of weighted multi-tape automata (WMTAs) in Natural Language Processing, that demonstrate the augmented descriptive power of WMTAs compared to weighted 1-tape and 2-tape automata. The two examples concern the preservation of intermediate results in transduction cascades and the search for similar words in two languages. As a basis for these applications, the article proposes a number of operations on WMTAs. Among others, it (re-)defines multi-tape intersection, where a number of tapes of one WMTA are intersected with the same number of tapes of another WMTA. In the proposed approach, multi-tape intersection is not an atomic operation but rather a sequence of more elementary ones, which facilitates its implementation.