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Re: Qualified Cardinality

From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
Date: Wed, 11 Apr 2001 19:31:23 -0400
To: bxk24@psu.edu
Cc: www-rdf-interest@w3.org
Message-Id: <20010411193123J.pfps@research.bell-labs.com>
Let me illustrate with an informal example.  Suppose I said that you had
(exactly) three siblings that would be using an unqualified cardinality
restriction.   If, however, I said that you had at least two siblings that
were doctors and (exactly) one that was a lawyer that would be using
qualified cardinality restrictions. 

Due to the difficulty of creating complex constructs in RDF without also
creating their component constructs, qualified cardinality restrictions use
cardinalityQ and hasClassQ.   If they used cardinality and hasClass, a
qualified cardinality restriction would have a piece that would be
interpreted as an unqualified cardinality restriction.  In the example
above, I would also have said that you have at least two siblings and
exactly one sibling, which is not what I wanted to say.

Peter F. Patel-Schneider
Bell Labs Research

PS: These extra ``keywords'' are not needed in representation languages
with a richer syntactic structure.   See OIL for an example.

From: "K. Boonserm" <bxk24@psu.edu>
Subject: Qualified Cardinality
Date: Wed, 11 Apr 2001 14:35:05 -0400

> Hi,
> I am confused about the different between the 'qualified' and 'unqualitied'
> cardinality and hasClass (e.g., cardinalityQ and cardinality, hasClass and
> hasClassQ)? If anybody can provide me explanation or pointer to other
> reading, I would be appreciated?
> thank you,
>  Boon
> ----------------------------------------------------------------------
> Boonserm (Boon) Kulvatunyou
> Industrial & Manufacturing Engineering PSU
> email: bxk24@psu.edu
> phone: 814-659-1963, 814-862-8509
> http://cim4.ie.psu.edu:12/serm/mypage.html
Received on Wednesday, 11 April 2001 19:32:14 UTC

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