Proving termination of a rewrite system by an interpretation over the natural numbers directly implies an upper bound on the derivational complexity of the system. In this way, however, the derivation height of terms is often heavily overestimated.#R##N##R##N#Here we present a generalization of termination proofs by interpretations that can avoid this drawback of the traditional approach. A number of simple examples illustrate how to achieve tight or even optimal bounds on the derivation height. The method is general enough to capture cases where simplification orderings fail.
['Dieter Hofbauer']
Termination Proofs by Context-Dependent Interpretations