Re: Re[2]: Associations in RDF

In a message dated 7/19/02 2:13:19 AM US Mountain Standard Time, leo@mmk.ru 
writes:
>  You are right ! And in practice we use a separate entity to model the
>  relations - associations . Although from formal logic point of view
>  they differ only as monadic and nonmonadic predicates.
>   But ! It will be helpful to take into account some
>  "relativity" between "properties" and "relations". Sometimes we model a
>  relation as "propertiy" of object and simetimes as separate entity
>  (see for example a discussion -
>  http://grouper.ieee.org/groups/suo/email/msg02014.html)
>  
>  As I wrote yesterday some more deep foundations must be taken into
>  account for basic Semantic Web metamodel.

Hi Leonid,

I agree with you and particularly think you characterized it well in
this part of the above post:

>>>
Yes , but some notes around an extension of the term "properties" .
Even in ODMG-93 standard they differ two types of properties as
"attribute"  type and as "relation" type. From this point of view such
property of a car as "colour" is "attrbute" type but such property as
"mark" is "relation" type (we "don't want" for example explicitly
include in our instance model a relationship with the car manufacturing
companies). BTW, it is important that a using of monadic and nonmonadic
predicates is relative (!).
<<<

This is precisely what I am suggesting for RDFS.

Best wishes,

 - Mike
----------------------------------------------------
Michael C. Daconta
Director, Web & Technology Services
www.mcbrad.com