[Sigia-l] Ontologies vs. DM-Even Longer-Sorry!

[Nuno Lopes]

Hi Lisa,

>I probably wouldn't create classes of individuals who
>are defined strictly on a relationship. So, "parent"
>would be a relationship between two individuals and
>"employee" would be the relationship between an
>individual and an organization. ("employer" could be
>defined as the inverse, but it's not necessary).

I see. But the fact is that you admit (this is how I interpret the word
"probably" in the beginning of the sentence) that the concepts of
Employee and Employer can be surrogated as Class entities (ask a
lawyer:). If they can, then they should be a class that is defined by
the relationship. 

To turn the problem more explicit the question is - Where would you put
the concept of Employment Contract? Should it be in the relationship?
Should it be it be in the [Person], in the [Organization]? 

If you admit that the concept of Employee can be mapped into a class
[Employee] then should it be within the definition of an Employee
(Employee Class) or should it be in the class [Employeer] by the same
reason?

In OOA and using UML we could:

	 Develops Role             Employment

[Person] --------- [Employee] --------.-------- [Employer] ...
   |                                  |
   | Develops Role                    |
   |	                            [Contract]
[Parent] .....


Any organization sees a Person as an Employee (is this a fact of being
person or of being an organization?). The Person when gets paid sees the
organization as an Employer only and not as an overall all complex
organic thing within an economy. But she does that according to an
Employment-Contract with as an Employer but it may be that other data
needs to be integrated within the equation. 

This kind of modeling allows new roles to be developed by the person
without changing the nature of being a person (as happens in real life).
The same thing can be said by the organization.

With Ontologies (Syc?)

[Person] ---- [Contract] ------ [Employer]
    |                                |
    ----------------------------------
      	Employment (transitive)

In categories (OOA):

So we have:

Human
	Person

Person Role
	Employee
	Parent

Organization
	Government
	Corporation

Organization Roles
	Employer


>What is in a name? Actually there is another "lisa
>colvin"! She is an IA in Los Angeles. I have been
>working mostly as an ontologist in the SF Bay Area.
>This is very confusing. I found out when we both
>applied for the same job! Pretty funny.  So,
>unfortunately, I can't answer any of your other
>questions.

I guess I go confused by some other post in another list. Sorry.

Best regards,

Nuno Lopes