Re: My task from last week: Semantic free identifiers

I agree with Chime points.  I will add that the great missing feature or
tool is versioning and depreciation handling.

I had a customer see a GUID URI once and freak out and almost drop a
contract.  Readability and maintainability is important.  Enforcing
uniqueness in literals is not part of the Semantic Web Standard, so it would
seem more ambiguity is introduced by relying on rdfs:label (note the
non-opaque uri in the rdfs standard) than relying on URI.  That is existing
tools allow for visualization and verification of URIs.  Even if we started
today, it would take a year it two to get our good tools to enable the
opaque sparql,etc support.

...from phone

On Jun 20, 2011 5:14 PM, "Sivaram Arabandi, MD" <sivaram.arabandi@gmail.com>
wrote:

Consider the following:

1. Readability - the former is far more readable than the later:
        RO:part_of
               vs.
       <http://purl.obolibrary.org/obo/RO_0000001>

   - this becomes even more apparent in a triple (CO = a 'Cardiology
Ontology'):
       CO:Mitral_valve   RO:part_of   CO:Heart
               vs.
       CO_01234556   RO_0000001   CO_01234554
               - doesn't make much sense (without tool support, which is
'practically' non-existent).

2.  Mistakes are extremely difficult to spot with opaque identifiers:
       CO_01234556   RO_0000001   CO_01224554
               vs.
       CO:Mitral_valve   RO:part_of   CO:Brain
               - this is an obviously false statement - but not easy to spot
if opaque identifiers were used.

       This leads to a very insidious problem, one that is difficult to
detect.

3. I am not sure why the following is an issue:

" Is my http://experiment the same as yours?
Is my http://gene? http://study?
Does my gene...
       - Obviously if I use "http://experiment" and you use "
http://experiment" we both are referring to the same thing.
       - But instead if I use "http://medicine/experiment"  and you use "
http://biology/experiment", we 'may' not be referring to the same thing.

4. When using readable identifiers, it is difficult to make changes to an
existing term (Class) - I think this is a strength as opposed to an issue.
It raises the bar and should encourage authors (of models) to create terms
thoughtfully after due diligence. And when there is a real need to change
the term i.e. its meaning has changed or it was inappropriate, ontology
patterns can be used to retire the term (if necessary, labelled as
deprecated) or reposition it.
       - 'Typos' in term names is definitely not a reason for having opaque
identifiers. Avoid them by having a good process for introducing terms. If
and when they occur, use ontology patterns to deal with them.
       - Using opaque identifiers with labels makes it very easy, almost too
easy, for the labels to be changed. Often times users of a model may not be
aware of such changes.


--Sivaram




On Jun 20, 2011, at 4:15 PM, M. Scott Marshall wrote:

> Hi Chime,
>
> The main reason is that w...