[topicmapmail] Contextualized Topic Maps.

[Murray Altheim]

Olivier Lamborelle wrote:
[...]
> As you say it yourself, it's the association that is scoped. Why XTM continues 
> 'pretending' that the Scopes on all the Roles of an Association [are expressed] 
> through a single <scope> subelement of the <association> element?

I'll have to think about this more, but I'm pretty sure the XTM spec
is correct on this in terms of the model. IOW, this is semantically
correct. I think this depends on how one models it.

> I agree that in the example you gave, the whole association looses sense if one 
> of the member is 'outscoped' but one can easily imagine a use for scoping each 
> member. Example: the association between a company and its employees in which 
> each employee is scoped by a period of time, during which it was employed (to 
> keep up with our times of flexible careers...).

I can understand what you're suggesting, but the semantics of
membership (i.e., employment) in a company are different than
the semantics of membership (i.e., being a Topic in a <member>
element) in a Topic Map Association. I believe it would be
incorrect to have one <association> element containing all the
employees of a company, unless the association type was a
collection. In that case, membership in the collection is defined
extensibly by the presence of the <member> and no scoping would be
possible (it seems to me that you'd be redefining the collection).
I think a more appropriate (or at least more straightforward) way
to model this would be to have a "Company X" Topic and associate
each employee Topic with an "isEmployeeOf" Association, which can
then be scoped. Employees don't really share the same Association
with their employer, they share the same Association *type*.

Murray

......................................................................
Murray Altheim                    http://kmi.open.ac.uk/people/murray/
Knowledge Media Institute
The Open University, Milton Keynes, Bucks, MK7 6AA, UK               .

    LEO (July 23-Aug. 22): When he first invented the printing press
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    going, you'll employ a wonderful new resource in a relatively
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