[sc34wg3] Association items

Lars Marius Garshol sc34wg3@isotopicmaps.org
Mon, 13 Jun 2005 08:45:26 +0200

* Murray Altheim
| In reading over your reply, I think you and I are perhaps using
| terminology differently, or understanding terminology differently.

I was using poor terminology, basically.
| "unary name" and "unary occurrence" are to my understanding (though
| I'd not term it this way) the way things are already done within a
| Topic Map. 

Yeah, I can see why you would think so, but what I meant was
"topicless name" and "topicless occurrence".

| If you accept the notion (ref Sowa) that a monadic predicate or
| unary association (basically the same thing, different terminology)
| is a fancy name for a property, and you consider a property as a
| synonym for a characteristic, then a Topic characteristic (of which
| name and occurrence are two instances) is related to the Topic via a
| unary association.
| [if that still doesn't make sense or we still disagree, let's then
| step back a bit and try again...]

It makes sense except for the unary association part. In a property
assignment there is the entity and the property value, but in a unary
association there is (in my view) only the entity and no property
value.  So to me the two cases seem different, but perhaps you
interpret this differently.
| In the grand scheme of entity relations, not everything considered an
| entity in the model. So if you're in, say, Protege, you don't want to
| have to add a new entity into the model if you just want to name an
| existing entity. So you give that existing entity a name, which is a
| kind of property. The relationship between the entity and its name is
| via a monadic predicate or unary association -- same basic thing --
| though "monadic predicate" is to be precise an indicator of the number
| of arguments in the relation.

So you are thinking that in the case of properties the second
argument, the string/number/whatever, does not count, and therefore
they are unary?

| No, by this I meant that if we hadn't provided element types like
| <basename> and <occurrence>, this could have been done via typed
| Associations. 

I know, but you would have had to extend the content model for
<member> to allow <resourceData> as a sub-element, since you can't
have an association between a topic and a string in XTM.

| Does this help? Get us closer to agreement or understanding?

Yes, I think it does.

Lars Marius Garshol, Ontopian         <URL: http://www.ontopia.net >
GSM: +47 98 21 55 50                  <URL: http://www.garshol.priv.no >