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Re: Equality of RDF bags

From: Pat Hayes <phayes@ihmc.us>
Date: Sat, 29 Oct 2011 14:37:25 -0500
Cc: semantic-web@w3.org
Message-Id: <BA654554-3680-4FD0-8EE2-30DED76D6C68@ihmc.us>
To: Heiko Paulheim <paulheim@ke.tu-darmstadt.de>

On Oct 28, 2011, at 1:59 AM, Heiko Paulheim wrote:

> Dear Pat,
>> The graphs are different.
> 
> that hits me. If I consider the following three graphs:
> 
> Graph 1:
> :b a rdf:Bag .
> :b rdf:li :ABook .
> :b rdf:li :AnotherBook .

rdf:li isnt meaningful outside RDF/XML, so in this graph it might as well be ex:whatever. So indeed. this graph is not equivalent to the other two. 

> 
> Graph 2a:
> :b a rdf:Bag .
> :b rdf:_1 :ABook .
> :b rdf:_2 :AnotherBook .
> 
> Graph 2b:
> :b a rdf:Bag .
> :b rdf:_1 :AnotherBook .
> :b rdf:_2 :ABook .
> 
> Given that the order of triples in an RDF document (especially in Graph 1) is considered not to be significant, is Graph 1 equivalent rather to 2a or 2b (while the latter two, as you say, are not equivalent to each other)?

No, all three are different graphs. But to emphasise again, this does not mean that they are describing different bags. The graph is only a *description*. The same thing - in this case, a small bag - can often be described in a number of different ways, all correct although different from one another. 

Pat

> 
> Thanks,
> Heiko.
> 
> 

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Received on Saturday, 29 October 2011 19:38:05 UTC

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