Re: RDF Semantics, non-lean RDF graphs, and redundancy of content

At 09:51 08/12/03 -0600, pat hayes wrote:
>>In addition, suppose I'm asserting the following:
>>
>><#pat> <#child> [ <#age> "4" ] , [ <#age> "3" ].
>
>? What does that mean? That the age is either 3 or 4? There is no way to 
>exactly model this in RDFS, though an ALT container would probably do as a 
>pragmatic device. Conforming RDF engines are not obliged to follow the 
>intended semantics of ALT, however.  (It is quite tricky to implement; 
>disjunctions raise the complexity level of inference to new heights.)

FWIW, that Notation3 expands out as this:

<#pat> <#child> _:a .
<#pat> <#child> _:b .
_:a <#age> "4" .
_:b <#age> "3" .

So no ALTS there, just two children.

#g


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Graham Klyne
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