Denote by sl-DT the class of superlinear deterministic top-down tree transformations, by REC the class of recognizable tree languages, and by DREC the class of deterministic recognizable tree languages. In this paper we present the following results. The class dom(sl-DT) is exactly the class of tree languages recognized by semi-universal deterministic top-down tree recognizers, which are introduced in this paper. Moreover, for any L € DREC, it is decidable whether L £ doni(sl-DT) holds and we

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... so present a decision procedure. Finally, we show that ra,nge(sl-DT) = REC.