Reasoning about typicality with low complexity Description Logics: the logic EL
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چکیده
We present an extension of the low complexity Description Logic EL ⊥ for reasoning about prototypical properties and inheritance with exceptions. We add to EL ⊥ a typicality operator T, which is intended to select the “most normal” instances of a concept. In the resulting logic, called EL ⊥ T, the knowledge base may contain subsumption relations of the form “T(C) is subsumed by P”, expressing that typical C-members have the property P . We show that the problem of entailment in EL ⊥ T is in co-NP by proving a small model result.
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