semantic web - Is the domain & range of owl:equivalentClass rdfs:Class or owl:Class? -

semantic web - Is the domain & range of owl:equivalentClass rdfs:Class or owl:Class? -

the domain , range of owl:equivalentclass raises questions have been unable locate answers.

first of all, in owl itself, domain , range of owl:equivalentclass set rdfs:class. domain , range seem clash definition given in spec (http://www.w3.org/tr/owl-ref/#equivalentclass-def), mentions that:

"the meaning of such class axiom [i.e. owl:equivalentclass] 2 class descriptions involved have same class extension (i.e., both class extensions contain same set of individuals)."

this suggests more specific domain , range of owl:class instead of rdfs:class (considering individuals mentioned rather instances).

using jena's reasoner engine, i've noticed owl inference rules contain next interesting elements: (1) axioms stating owl:equivalentclass has domain , range owl:class (2) rule 2 resources rdfs:subclassof each other must owl:equivalentclass each other.

so, basically, here domain , range restricted owl:class, seems understandable. if domain , range narrowed downwards that, though, shouldn't rule @ (2) confined state both resources should of type owl:class in order entail owl:equivalentclass relation? after all, rdfs:subclassof relation can work on rdfs:classes. if classes subclasses of each other rdfs:classes, certainly - if definition of owl:equivalentclass has been narrowed downwards in (1) - rule should not imply rdfs:classes owl:classes.

does know reply right interpretation of owl:equivalentclass, perchance providing authoritative source?

thanks in advance!

the relevant document owl 2 web ontology language rdf-based semantics (second edition). section 6.4 gives axiomatic triples rdf-based semantics, , includes triples specify domain , range of owl:equivalentclass rdfs:class:

6.4 set of axiomatic triples table 6.2: axiomatic triples properties of owl 2 rdf-based vocabulary owl:equivalentclass rdf:type rdf:property . owl:equivalentclass rdfs:domain rdfs:class . owl:equivalentclass rdfs:range rdfs:class .

note owl has direct semantics doesn't create utilize of rdf @ all. defines semantics in terms of sets of individuals (for classes) , sets of pairs of individuals (for properties). in case, there'd no concept of owl:equivalentclass beingness property rdfs:domain , rdfs:range @ all.

as reasoning jena, jena's reasoners designed around owl1, not owl2, if there's important difference in part of spec, jena closer owl1 spec. jena's reasoners also, far recall, more designed toward owl total owl dl, , might not care much preserving difference between rdfs:class , owl:class.

semantic-web owl inference equivalence equivalence-classes