ORACLES IN $\Sigma^p_2$ ARE SUFFFICIENT FOR EXACT LEARNING
Johannes Köbler, Wolfgang F. Lindner · International Journal of Foundations of Computer Science · 2000
We study the learnability of representation classes in Angluin's exact learning model. In particular, we consider the following three query types: equivalence queries, equivalence and membership queries, and membership queries only. We show in all three cases that polynomial query complexity implies already polynomial-time learnability, provided that the learner additionally has access to an oracle in [Formula: see text]. It follows that boolean circuits are polynomial-time learnable with equivalence queries and the help of an oracle in [Formula: see text].a