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[protege-owl] auto-updating instances after changing a property to transitive or symmetric?
mi.wessel at tuhh.de
Tue Sep 5 09:50:29 PDT 2006
On Monday 04 September 2006 15:52, dimitris bilidas wrote:
> Let's say that we have a property P with domain and range the same class C.
> We also have the instances I1, I2 and I3 of the class C. The instance I1 is
> related through the property P with the instance I2, and the instance I2 is
> related through the property P with the instance I3.
> After these, we declare the property P transitive. Shouldn't the instance
> I1 get a relation through the property P with the instance I3? This doesn't
> happen automatically. Furthermore, when I am checking the ontology for
> consistency(I used both pellet and racer), I get no errors, though I1 is
> not related with I3. Shouldn't the model be inconsistent?
No. In the *logical* models of the OWL KB, I1 and I3 will be P-related (the
fact P(I1,I3) holds). The fact P(I1,I3) is logically implied (entailed). An
absence of P(I1,I3) from the OWL KB is (in general) not interpreted as NOT
P(I1,I3), unlike in databases (this is called the open world assumption, in
contrast to the closed world assumption). Thus, everything is okay.
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