Determinacy and subsumption for single-valued bottom-up tree transducers

Abstract

This paper discusses the decidability of determinacy and subsumption for tree transducers. For two tree transducers T 1 and T 2, T 1 determines T 2 if the output of T 2 is identified by the output of T 1, that is, there is a partial function f such that where and are tree transformation relations induced by T 1 and T 2, respectively. Also, T 1 subsumes T 2 if T 1 determines T 2 and the partial function f such that can be defined by a transducer in a designated class that T 2 belongs to. In this paper, we show that determinacy is decidable for single-valued linear extended bottom-up tree transducers as the determiner class and single-valued bottom-up tree transducers as the determinee class. We also show that subsumption is decidable for these classes. © 2013 Springer-Verlag Berlin Heidelberg.