Thanks to Pete for correcting the impression I gave, and confirming 
the suspicion that one can indeed take the approach I've 
characterised as "Topic Map" to portfolio relationships, using RDF. 
It would be very interesting to take this forward and work out just 
what would be involved in total. Has anyone done something like this 
in this, or a similar domain? How, exactly? Could it be described (or 
thought of) as 'lite'?

My not understanding the point fully was due to seeing many examples 
of RDF where the relationship triples are indeed put inside one of 
the sides. Given that FOAF has had a rather high profile, and this is 
what seems to be what is normally done there, it's good to have it 
clarified that it is not the only way.

On the Topic Maps front, there is a clear, self-contained format 
(XTM) in which all of the relationships could be represented. I'm 
looking for what would be done with RDF to implement a similar approach.

Thanks

Simon

At 15:41 2006-09-21, you wrote:
>Hi Simon,
>
>Just leaping in on one point...
>
> > 3. The RDF approach
> > You embed all relationship information in each appropriate
> > element, but the related elements stay separate, each with
> > its own embedded relationship information. Whether you have
> > both ends of a relationship represented is a good question.
> > If you don't, then which end is chosen to hold the
> > relationship information? And what happens if the
> > relationship is noted at both ends, but the ends don't agree?
>
>I'm not sure I agree with your characterisation of the RDF approach, but
>maybe I am misunderstanding what you are implying by "embed".
>
>For the non-initiates, RDF allows you to construct simple three "word"
>statements where each word is a URI, and the statement is to be read as
>an assertion that
>
>resource-identified-by-first-URI is-related-in-a-way-indicated-by-the
>second-URI to resource-identified-by-second-URI
>
>Using RDF on the Web, "anyone can say anything about anything", and
>given that the RDF model is fundamentally one of assertions of binary
>relationships, "anyone can assert the existence of any relationship
>between any two things".
>
>So I am not limited to making assertions about resources I own or which
>I have write access to.
>[...]