[sc34wg3] Identifying and comparing subjects (and a possible extension to \tau )

Steven R. Newcomb sc34wg3@isotopicmaps.org
02 Aug 2004 15:57:15 -0400

Ann Wrightson <ann.wrightson@csw.co.uk> writes:

> I believe
> that there should also be a different operation that both preserves the
> original maps and defines a view-as-if-merged-according-to-this-mapping. 

> I'm realizing as I write that this suggests a different formal account of
> merging - call it merge2 - eg (in \tau) where the two maps being merged have
> different sets of names (curly N1 and N2) in the universe (curly I) and
> instead of merge2 being a set union, it is a function where the desired
> property of "preserving information" from the source maps to the target maps
> becomes a morphism property of the function.

I think maybe your proposal is satisfiable by use of the "conferred
property value component" facility of the current TMRM.  A TMA ("TMA
C") that discloses the bases on which topic maps governed by two other
TMAs ("TMA A" and "TMA B") are viewable as having been merged, is
defined as follows:

  TMA C "includes" TMA A.  (I.e., it knows about TMA A-governed

  TMA C "includes" TMA B, too.

  For some or all of the SIPs defined by TMA A, TMA C regards them as
  triggering the conferral of values on SIPs (defined by TMA C) of the
  very same proxies.

  Same goes for some or all of the SIPs defined by TMA B.

  The merging rules defined (by TMA C) for the SIPs defined by TMA C,
  and the conferral rules defined by TMA C that confer values on them,
  are so contrived that, whenever it's appropriate, the proxies merge,
  even though their TMA A-governed SIPs and TMA B-governed SIPs don't,
  under those two TMAs, demand merging.

Confidential to everybody except Ann: While writing the above in my
hotel room at Extreme, the phone rang.  It was Ann; she was creating a
poster for the poster session on exactly the above.  We put our heads
together and the result was a set of slides (for posting here at
Extreme) that illustrate the above concept, using the real-world
example of medical records that use two different coding systems:

-- Steve

Steven R. Newcomb, Consultant
Coolheads Consulting

Co-editor, Topic Maps International Standard (ISO 13250)
Co-drafter, Topic Maps Reference Model 


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