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Linked Stuff [was Re: RDF's challenge]

From: David Booth <david@dbooth.org>
Date: Tue, 11 Jun 2013 13:59:55 -0400
Message-ID: <51B7659B.30904@dbooth.org>
To: Kingsley Idehen <kidehen@openlinksw.com>
CC: public-lod@w3.org
On 06/11/2013 12:18 PM, Kingsley Idehen wrote:
> On 6/11/13 11:56 AM, David Booth wrote:
>> On 06/11/2013 10:59 AM, Kingsley Idehen wrote:
>>> [ . . . ]  many RDF advocates
>>> want to conflate Linked Data and RDF. This is technically wrong, and
>>> marketing wise -- an utter disaster.
>> I have not heard RDF advocates conflating Linked Data and RDF, but
>> maybe you talk to different RDF advocates than me.
>> AFAICT, the vast majority of RDF advocates know that Linked Data is
>> RDF in which URIs are deferenceable to more RDF, but RDF is not
>> necessarily Linked Data, because RDF itself does not require URIs to
>> be dereferenceable.
>> David
> RDF isn't the defining characteristic when speaking about Linked Data
> outside the RDF community.

But RDF *is* one of Linked Data's defining characteristics, regardless 
of whether people outside the RDF community understand that.  (And it 
seems to me that if they don't understand that, then we should help them 
to understand that, rather than perpetuating their misunderstanding.)

> It is much more palatable outside of the RDF
> community to loosely couple Linked Data (the concept) and RDF (a
> framework) which enables the construction of powerful Linked Data that's
> endowed with *explicit* human and machine-comprehensible entity
> relationships semantics.

We could define a new concept that decouples RDF from Linked Data.  But 
to avoid conflating Linked Data with this new notion, let's call this 
new notion "Linked Stuff":

   DEFINITION: **Linked Stuff** is data that uses URIs to
   identify things, and those URIs are dereferenceable to
   more Linked Stuff that describes those things.

There may be some good marketing benefit in adopting this simple notion 
of Linked Stuff, since it avoids any mention of RDF, but there would be 
a very important technical loss as well, in comparison with Linked Data. 
  To understand that loss, suppose a client application has some Linked 
Stuff and wants to learn more about the thing identified by one of the 
URIs in it.  The client application automatically dereferences that URI 
and receives more Linked Stuff.  But can the client application 
understand or do anything with the document that it receives?  Not 
necessarily, because that document may be in some random 
tab-separated-values form, that the client application has no idea how 
to interpret.

Compare this with Linked Data.  In the Linked Data case, the client 
application receives RDF.  The document does not necessarily *look* like 
RDF (to an untrained eye), because RDF is syntax independent, and there 
are many different serializations of RDF.  But as long as some kind of 
standard RDF serialization was used -- even XML-based serializations 
that use GRDDL[1] -- the client application is able to interpret and 
make use of that document.

This is the goal of the Semantic Web: to enable machines to usefully and 
(semi-)automatically, find, share, combine and process web data. 
Because Linked Data is RDF, Linked Data supports that goal in a very 
important way that Linked Stuff does not.


1. GRDDL: http://www.w3.org/TR/grddl-primer/

> Why? Because you don't build friction with folks that are already
> familiar with similar concepts albeit described using different
> terminology.
> The key is to build bridges rather than impede their construction by
> enforcing world views in the most inflexible way.
> If someone indicates to you that the letters R-D-F don't work for them,
> for whatever reason, what's wrong with triangulation to the same
> destination when it's the fundamental concept that matters, not the
> labels that we slap on them at specific times in our innovation continuum?
> RDF and the Entity Relationship model [1] outlined by Peter Chen in his
> 1976 dissertation are linked, conceptually and technically. That
> association is very powerful and extremely useful in situations where
> your audience suffers from R-D-F reflux.
> RDF is useful, but it (like all innovations) has genealogy. That
> genealogy is just as important as the innovations it adds to the continuum.
> Links:
> 1. http://bit.ly/YTdz3N -- The Entity-Relationship Model -- Toward a
> Unified View of Data  (note: page 34) .
Received on Tuesday, 11 June 2013 18:00:23 UTC

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