Preservation of Recognizability for Weighted Linear Extended Top-Down Tree Transducers
Nina Seemann, Daniel Quernheim, Fabienne Braune, Andreas Maletti · 2012
An open question in [Fulop, Maletti, Vogler: Weighted extended tree transducers. Fundamenta Informaticae 111(2), 2011] asks whether weighted linear extended tree transducers preserve recognizability in countably complete commutative semirings. In this contribution, the question is answered positively, which is achieved with a construction that utilizes inside weights. Due to the completeness of the semiring, the inside weights always exist, but the construction is only effective if they can be effectively determined. It is demonstrated how to achieve this in a number of important cases.