Equivalence of Symbolic Tree Transducers

Symbolic tree transducers are programs that transform data trees with an infinite signature. In this paper, we show that the equivalence problem of deterministic symbolic top-down tree transducers (DTop) can be reduced to that of classical DTop. As a consequence the equivalence of two symbolic DTop can be decided in NExpTime, when assuming that all operations related to the processing of data values are in PTime. This result can be extended to symbolic DTop with lookahead and thus to deterministic symbolic bottom-up tree transducers.