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Re: New RDF model theory (well, damn nearly)

From: <jos.deroo.jd@belgium.agfa.com>
Date: Thu, 16 Aug 2001 18:09:58 +0100
To: phayes@ai.uwf.edu
Cc: w3c-rdfcore-wg@w3.org
Message-Id: <OFD1DBA542.1D57BC3E-ON41256AAA.005ABA2A@bayer-ag.com>

[It's even better now with the exercises, so let's try]

[...]
> Exercise: Calculate the truthvalues of the triples
> c a c
> b b b
> c b a
> in this interpretation.

c a c false
b b b false
c b a true

> More advanced exercise: Write six distinct triples in
> this vocabulary and define another interpretation which
> makes three of them true and the other three false.

six distinct triples (true in the given interpretation)
  a b c
  b b c
  c b b
  a a c
  c a a
  c a b
and the interpretation
  IR={1,2}; IP={1}
  IEXT:1->{<1,2>}
  IS:a->1,b->1,c->2
gives only true triples
  a b c
  b b c
  a a c

[...]
> Exercise:  Consider the RDF graph defined by the following triples:
> _:x a b
> c b _:x
> _:x a c
>
> Is this graph true or false in the interpretation given in the
> previous exercise?

false
(triple 1 and triple 3 can not be both true)

> How about the graphs formed from just the first triple, and from
> just the last two triples?

both true

--
Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
Received on Thursday, 16 August 2001 12:10:28 EDT

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