Re: ISSUE-66: LinkedData™

Hi John,

On 08/05/2014 03:21 PM, John Walker wrote:
> Hi Dave
>
> How about an official W3C Linked Data Primer to expand upon the ideas
> presented in the glossary?

There is a draft Linked Data Platform Primer:
http://www.w3.org/TR/ldp-primer/

But I think a more general Linked Data primer could certainly be helpful 
also.  Are you volunteering to start a draft?  :)

>
> I know there is the Best Practices for Publishing Linked Data [1] but
> that seems to be aimed at a more specific audience.
>
> Also I think the work Ruben et al. Are doing is proof that SPARQL is
> not the only way to query the web of data, so getting the wording
> right here is important. Avoiding a lot of the acronyms and
> abbreviations, or introducing them gradually, would help make such a
> document more accessible to the Linked Data™ n00b.

I personally agree, and I hope he'll succeed in drafting something that 
reaches consensus.  But I would also advise caution, since such an 
effort can snowball unexpectedly.

David

>
> [1] http://www.w3.org/TR/ld-bp/
>
> Regards,
>
> John
>
> On 5 Aug 2014, at 21:02, David Booth <david@dbooth.org> wrote:
>
>> On 08/05/2014 05:07 AM, Ruben Verborgh wrote:
>>> Hi all,
>>>
>>> Jumping in, as this is very relevant for the Linked Data
>>> Fragments spec [1]. In fact, this issue appearing after I drafted
>>> an introductory section called “What Linked Data is” might not be
>>> a coincidence. (And it's very good timing in any case.)
>>>
>>> Let me start out by saying I was totally oblivious of ”non-RDF
>>> Linked Data”.
>>
>> That's like saying you were totally oblivious to the existence of
>> the non-URI based World Wide Web.   There's a good reason why you
>> were oblivious to their existence: they do not exist!
>>
>>> I.e., I had always assumed that Linked Data is in RDF; probably
>>> because Tim's original principles explicitly mention this [2].
>>> Then again, we all know the principles are quite vague: - RDF*
>>> and SPARQL are mentioned between parentheses. Did this mean
>>> "e.g., RDF*, SPARQL", or "i.e., RDF*, SPARQL"? That's an
>>> important difference, and we'll likely never know. - Where is the
>>> asterisk after RDF ever resolved? Maybe I just missed the
>>> majority of the discussion; i.e., posts like [3] were written in
>>> 2009.
>>>
>>> That said, me being in the community for 4 years and never
>>> having heard about (or being selectively deaf towards) non-RDF
>>> Linked Data, means something at least. I'd dare to say that the
>>> majority of people do assume that Linked Data is just done with
>>> RDF. So to what extent is it then necessary to clarify this?
>>
>> Unfortunately, it has become painfully evident that there are a few
>> people who do not realize that Linked Data implies RDF (or who wish
>> that it didn't).  For this reason, I think it is important to be
>> clear about it.
>>
>>>
>>> In that context, Dan Brickley sent a useful comment to me: “RDF
>>> is to Linked Data as HTML is to the classic Web, maybe”.
>>>
>>>>> i was specifically trying not to get that discussion going.
>>>>> just asking whether there should be some
>>>>> definition/clarification of the term, just to let readers
>>>>> know what it means in the context of the spec/community. if
>>>>> you define a broad term to mean a narrow thing, then this
>>>>> might be helpful to avoid possible confusion.
>>>
>>> What do you think about the current introduction to the triple
>>> pattern fragments spec [1]? Not knowing about this issue yet, I
>>> phrased it as:
>>>
>>> By publishing Linked Data [LINKED-DATA], we enable automated
>>> clients to consume information. In practice, this information is
>>> available as RDF triples […]
>>>
>>> So it leaves the question open whether non-RDF Linked Data
>>> exists; it just says that, in practice, it will be RDF. Good
>>> enough?
>>
>> No.  It is important to *not* leave that question open.  That was
>> the whole point of the huge debates that occurred about this --
>> debates that (thankfully) finally ended with the official
>> publication of the W3C Linked Data Glossary.
>>
>>>
>>>> I think a definition could help.  I suggest copying the one
>>>> from the W3C Linked Data Glossary verbatim (and referencing
>>>> that document), rather than trying to craft a new one and
>>>> risking another long debate about what it should be.
>>>
>>> Sadly, I think that definition is quite complicated. Here it is
>>> at full length, copied from [4]:
>>>
>>> Linked Data
>>>
>>> A pattern for hyperlinking machine-readable data sets to each
>>> other using Semantic Web techniques, especially via the use of
>>> RDF and URIs. Enables distributed SPARQL queries of the data sets
>>> and a browsing or discovery approach to finding information (as
>>> compared to a search strategy). Linked Data is intended for
>>> access by both humans and machines. Linked Data uses the RDF
>>> family of standards for data interchange (e.g., RDF/XML, RDFa,
>>> Turtle) and query (SPARQL). If Linked Data is published on the
>>> public Web, it is generally called Linked Open Data. See also
>>> [Linked Data Principles].
>>>
>>> It forces you to understand: - Semantic Web - RDF - URIs - SPARQL
>>> to make sense out of it.
>>>
>>> And personally, I wonder to what extent SPARQL is part of Linked
>>> Data; and does that mean the query language, the protocol, or
>>> both?
>>
>> I agree that that definition is not ideal.  And maybe you could
>> come up with a simpler definition that would be acceptable.  But
>> please be aware that the term "Linked Data" is very important to
>> the semantic web community, and there are people with strong
>> feelings about it, so crafting an alternate definition runs a risk
>> of long debates.
>>
>>>
>>> On the technical level, nothing prohibits us from making Linked
>>> Data Fragments broader than RDF. We'd have to be very careful,
>>> however, that the concept would still be sufficiently meaningful;
>>> that it doesn't become hollow by broadening it.
>>>
>>> For triple pattern fragments, by definition, we are limited to
>>> the RDF triple model. That does not mean that other kinds of
>>> fragments would have such a strong dependency; so other fragment
>>> types we define might be independent of RDF.
>>
>> I don't see a fundamental problem with that if there is sufficient
>> motivation for it.  Even though LDF was designed for Linked Data, I
>> think it would be okay if it also happens to work with *other*
>> data. But it is important to avoid implying that there is any such
>> thing as "non-RDF Linked Data", because that would just cause
>> confusion and reignite unnecessary debates.
>>
>> David
>>
>>>
>>> Best,
>>>
>>> Ruben
>>>
>>> [1] http://www.hydra-cg.com/spec/latest/linked-data-fragments/
>>> [2] http://www.w3.org/DesignIssues/LinkedData.html [3]
>>> http://cloudofdata.com/2009/07/does-linked-data-need-rdf/ [4]
>>> http://www.w3.org/TR/ld-glossary/#linked-data
>>>
>>>
>>
>
>
>

Received on Tuesday, 5 August 2014 19:43:48 UTC