We investigate the complexity of learning query inseparable ELH ontologies in a variant of Angluin's exact learning model. Given a fixed data instance A_* and a query language Q, we are interested in computing an ontology H that entails the same queries as a target ontology T on A_*, that is, H and T are inseparable w.r.t. A_* and Q. The learner is allowed to pose two kinds of questions. The first is 'Does (T, A) |= q?, with A an arbitrary data instance and q and query in Q. An oracle replies this question with 'yes' or 'no'. In the second, the learner asks 'Are H and T inseparable w.r.t. A_* and Q?'. If so, the learning process finishes, otherwise, the learner receives (A_*, q) with q ∈ Q, (T, A_*) |= q and (H, A_*) |≠ q (or vice-versa). Then, we analyse conditions in which query inseparability is preserved if A_* changes. Finally, we consider the PAC learning model and a setting where the algorithms learn from a batch of classified data, limiting interactions with the oracles.
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