Re: [OEP] Draft of a note on n-ary relations

> Some remarks about Pattern 2.
>
> - The property "amount" seems to me a Datatype property, but it is  
> displayed in the
> graphical representation
> the same way as otherwise Object properties, and further on not  
> mentioned in the
> restrictions.
> So it does not seem to really participate in the relationship, or in a  
> different and
> underspecified way.
> This is potentially confusing.
> I would suggest to either get rid of it altogether (the example seems  
> complex and
> illustrating enough without it),
> or specify how "amount" is different from other roles in the  
> association. (Sorry, topic
> map terminology is coming here very naturally - see below).

I favor getting rid of it. This would mean using something other than  
purchase though (seems unnatural to define a purchasing event without  
an amount -- yo are right it doesn't add anything and only creates the  
confusion, but still). Perhaps borrowing or something like that.

> - Why is there not any inverseOf for "purpose"?

No reason, except that it didn't seem to be natural to have one.  
Perhaps it should be there.

> - The pattern looks much topic-map-ish to me ... A translation in  
> terms of Topic, Roles
> and Associations is quite obvious and easy to do. Note that in a topic  
> map representation,
> the inverse properties would be useless, since the linking of a topic  
> to an association
> through a role is by nature two-ways.
> Only the instance of Purchase could be expressed easily this way in  
> XTM, while the
> reference pattern could be in the OWL ontology. I made proposals for  
> such mechanism in my
> XML Europe 2004 paper "Ontology-Driven Topic Maps"
> http://www.idealliance.org/europe/04/call/xmlpapers/03-03-03.91/.03 
> -03-03.html
>
> I can provide TM translation for the Lionish example, along the lines  
> of this paper, and a
> bit of XTM syntax if it considered relevant to include it in the  
> document.

this would indeed be useful (Alan?). Could you make a pass at it? It  
would help though if you use an example very similar to the one in the  
note -- perhaps the same one (says she, right after saying she is going  
to change it :)

Natasha

Received on Wednesday, 5 May 2004 21:27:36 UTC