This is a wonderful discussion, and very apropos for this list. As we
think about "semantic web use cases" for HCLS, we find that our
imaginations need just this kind of stretching to conceive of good
applications -- not because applications don't exist (in spades) --
but because we're just discovering them, and so finding them means
breaking old thought habits.
There's an important point that comes out of this about how to
discuss SW with "nonbelievers". Some ask "What is it that the SW can
do, that I can't do with ..." (fill in the blank: database merging,
data modeling standards, schema languages, blah blah).
(I happen to be out at SMI at a Protege course at the moment and
Jennifer Vendetti made exactly this point about ontologies, so I'm
shamelessly stealing her point...)
One true answer to this question is "nothing". Another true answer is
"many, many things!!"
"Nothing" ---> RDF/RDFS/OWL are formally equivalent to a subset of
what can be expressed in relational database language. RDBMS are in
this sense "more powerful" than any "semantic web language". (I think
this is what Vipul meant when he said that moving knowledge out onto
the web does not "add any semantics".)
"Many,, many things": RDF/RDFS/OWL make *your* assertions accessible
to hundreds of millions of people, who can add their own assertions.
Millions of new assertions about your resource --- even if any
individual one is not incremementally very information-rich -- can
collectively be worth a lot more than a mere handful of "strong"
assertions that only a few people can "see". (And if the former
requires minimal effort on any one person's part, and the latter
requires herculean effort on one person's part, then the former is a
lot more likely to happen than the latter.) (This is (I think) what
Jim means by a little goes a long way.)
The point is, the original question is phrased in an unhelpful way.
The real question is not "what can it do", but "does it make
interoperability easier, and hence the creation of useful semantic
communities more likely". And these new semantic communities will
change the way we do health science, and the way we live -- and hence
how they will look is hard to conceive of in advance !!!!
John
On Mar 31, 2006, at 1133, John Barkley wrote:
I believe there is an additional advantage beyond semantics and the
"web".
I would suggest that the quality of information models can be
significantly
improved using semantic web methods and tools as compared to those
developed
using other methods in common use, e.g., relational, XML, UML. With
semantic web methods and tools, more of an information model can be
made
explicit in a formal language while the model remains amenable to
automated
validation and testing. In other words, things about an information
model
that can only said implicitly with other methods (e.g., in
documentation)
can be said explicitly with semantic web methods while still
maintaining the
capability for applying fully automated validation and testing to
the model.
The reason for this is the work that has been done in the theory of
Description Logic on which the semantic web rests. Description logic
provides the foundation on which formal languages for describing
information
models may be defined. RDF/OWL is the standard description logic
formal
language of the semantic web.
Thus, as you know, a knowledge base described in RDF/OWL has the
following
characteristics:
1. Whether the knowledge base is amenable to automated
validation and
testing can be readily determined by a grammatical examination of the
features of RDF/OWL used in the description. OWL DL is the
sublanguage of
RDF/OWL which supports automated validation and testing.
2. Given that a knowledge base is amenable to automated
validation and
testing, a fully automated "reasoner" can used to perform such
validation
and testing.
Specification of an information model in a formal language with the
certainty that the validity of such a specification can be tested
automatically can go a long way in improving the quality of the model.
jb
----- Original Message -----
From: "Kashyap, Vipul" <[EMAIL PROTECTED]>
To: "Danny Ayers" <[EMAIL PROTECTED]>
Cc: "Jim Hendler" <[EMAIL PROTECTED]>; "deWaard, Anita (ELS)"
<[EMAIL PROTECTED]>; <public-semweb-lifesci@w3.org>
Sent: Friday, March 31, 2006 8:08 AM
Subject: RE: Ontology editor + why RDF?
I saw a quote not long ago, not sure of the source (recognise this
Jim?), approximately: "what's new about the Semantic Web isn't the
semantics but the web".
[VK] This is a great quote and expresses clearly that the value
proposition
in representing and linking vocabularies using URIs stems from
the
Web more than "semantics"
I take VK's point that this in itself isn't going to convince many IT
folks. I think the big persuader there is data integration, even on a
sub-enterprise kind of scale.
[VK] Agreed, one of the clearer value propositions is data
integration.
Being able to use ontologies to infer new information is a massive
plus (I imagine especially in the lifesciences). Bigger still are the
(anticipated) benefits of the Semantic Web when the network effect
kicks in. But the ability to use RDF to simply merge data from
multiple sources consistently (and query across it), without needing
complete up-front schema design is a very immediate, tangible gain.
The work done around SKOS (and specific tasks like expressing WordNet
in RDF) does suggest RDF/OWL is a particularly good technology choice
for thesauri.
[VK] Danny, has articulated some potential benefits:
- Network effects
- Schema-less linking based data integration
I would argue that both these benefits stem from the web
infrastructure and
have
nothing to do with the "semantics" of anything per-se.
Also, one could argue that having a standardized markup language
whether it
be even HTML or XML enables the above to a significant extent.
So the value proposition question could be:
What is it about RDF that enables network effects and schema less data
linking
better than HTML, relational tables or XML in a more significant
manner?
Is the improvement enabled v/s the cost required to achieve it an
attractive
trade off?
Look forward to yours and the groups responses to these questions.
Cheers,
---Vipul
