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Re: AWWSW status (F2F prep)

From: Harry Halpin <hhalpin@ibiblio.org>
Date: Wed, 17 Mar 2010 20:48:47 +0000
Message-ID: <b3be92a01003171348y4a6ff1c4id5b624a383869f73@mail.gmail.com>
To: David Booth <david@dbooth.org>
Cc: Jonathan Rees <jar@creativecommons.org>, www-tag@w3.org
Yes, I agree this is important work. Myself and Valentina Presutti and
Aldo Gangemi will hope to get alignment between our IRW ontology work
and the valuable work of the AWWSW TAG.

On Wed, Mar 17, 2010 at 8:10 PM, David Booth <david@dbooth.org> wrote:
> Excellent summary!
> David
> On Wed, 2010-03-17 at 14:15 -0400, Jonathan Rees wrote:
>> AWWSW status (F2F prep)
>> The AWWSW group was started because Alan Ruttenberg and I were doing
>> quite a bit of ontology design and ontology advising and didn't
>> understand the resource/representation relationship (and the
>> "information resource" idea, which is intimately bound up with it)
>> well enough to do our work or guide others.  The question comes up
>> when you have things that you want to give a URI to, and you want to
>> use 200 responses (non-# non-303 URI), but want to be protected
>> against someone coming along later and saying "hey, that's not an
>> information resource," or "but you said it's an IR, and that implies
>> xxx" where you don't mean to say xxx, or "that's an IR, but not the one
>> you want it to be".
>> This is dual (equivalent) to the question: Suppose you get 200
>> responses, is it OK to then decide that the named resource
>> is some particular thing or has certain properties?  E.g., if I am
>> the owner of dx.doi.org, can I say that the URI
>> http://dx.doi.org/10.1093/bib/bbn051 names the journal article
>> that's indicated in the representation (so that I can license others to use
>> the URI when recording metadata)?  (Note that this is a subtle
>> example.  The httpRange-14 rule by itself is not adequate to rule this in or
>> out.  In particular the representation might fail to be "of" the
>> journal article even if we decide the journal article is an IR.  Also
>> there is redirection involved, which complicates things further.)
>> Alan and I approached the TAG, which said essentially "you figure it out."
>> (Shortly thereafter I discovered that I was on the TAG.)
>> Some ontologies where this is an issue include FRBR, Dublin Core,
>> Bibo, SWAN, CiTO, IAO, and IRW, but as the practice of metadata
>> deployment, document and media annotation, etc. increases
>> (perhaps with the help of the Link: header?), I expect there to be
>> many more.
>> A broader motivation, which I share with TimBL, is that if we had a
>> logical framework (perhaps expressible in RDF or OWL), we'd have a
>> tool that we could use to help clear up a number of number of web
>> architecture muddles.  httpRange-14 is just an example; another
>> recent one on www-tag was "are HTML elements information
>> resources?"
>> A third motivation is that an RDF vocabulary for webarch could be
>> useful in a number of application domains, e.g. testing and
>> validation, or recording change logs (e.g. Memento), or "HTTP over
>> SPARQL", or further developing Tim's generic resources ontology
>> (genont).
>> Additional concerns have been raised in the group about how
>> URIs might become bound to things, but I have not pursued
>> this (yet). My current theory is that URI binding is a personal matter
>> subject to your belief set, and how you come to that is your
>> own business. You may choose to let what happens on the
>> Web influence your beliefs, and there may be a recommended
>> elective way to allow this to happen, and
>> perhaps an outcome of this project, in the future, might be
>> such a way.
>> I can't say we've made a lot of visible progress, but I think I do
>> understand the problem better now that I did before.
>> First, Roy Fielding is right: We're not just talking about HTTP
>> semantics, but rather the semantics of that part of web architecture
>> that is expressible in HTTP.  This includes the
>> resource/representation relationship, the various redirects (including
>> 303), and possibly existence (creation and deletion).  I think webarch
>> as deployed might include REST as a subset, but certainly there are
>> resources deployed using GET+200 that do not obey REST discipline, and
>> we need to account for these somehow.
>> Second, TimBL has provided more information about his view of what is
>> and isn't an information resource, and he thinks they're like.  I have
>> been unable so far (my
>> inadequacy) to combine these use cases with other constraints (such as
>> grandfathering all possible web pages) into an actionable definition
>> that makes sense to me, but I continue to work at it.
>> Third, "authoritative" per the updated http: URI scheme in HTTPbis is,
>> I think, orthogonal to the R/R problem.  The "authoritative" responses
>> do not determine the resource uniquely, they only say that it belongs
>> to a class of resources that participate in the R/R relationships
>> communicated by the responses.  A contradiction between an
>> "authoritative" response and other information believed about the
>> resource might lead you to discount the "authoritative" response (as
>> recommended by the GBIF persistent identifiers report) or to
>> stop using that URI to name the resource, just as easily as it might
>> lead you to doubt what you thought you knew about the resource.
>> Of course, the ability of an agent to speak HTTP-authoritatively about
>> a resource may be due to the agent's ability to control the resource
>> and therefore its "representations". For these particular resources,
>> the R/R relationship holds because the agent says so. For others
>> (such as Moby Dick) it might hold in spite of what the agent says.
>> I am concentrating on the resource/representation relationship.  My
>> ambition is that if we have a story about when this holds and doesn't
>> hold - in particular how to falsify it - then answering the
>> question "what is an information resource" will fall out as a side
>> effect: an IR is simply something which happens to be able to
>> participate in this relationship.
>> So far the best lead I've encountered so far in understanding the
>> relationship is ABLP logic, as is being pursued by Dan Connolly.  It
>> may be that ABLP can't be used directly, as convincing someone that a
>> web page is a principal, or that "principal" has any ontological
>> consequence, might be a tough sell.  Or it may be that this, too, is
>> an ontological wild goose chase, or that ABLP is about
>> the URI/resource relationship instead of the resource/representation
>> relationship.  But it's worth pursuing.
>> Open issues on which these considerations impinge:
>>   ISSUE-50 URNs and registries - persistence vs. trust in "authority"
>>   ISSUE-57 HTTP redirections - consequences of 30x
>>   ISSUE-63 metadata architecture - metadata for http:-named resources
>>   ISSUE-53 generic resources (appears to be closeable)
>> Next step (for me): Look in more detail at the kinds of metadata,
>> including class memberships, one might want to write using the
>> abovementioned ontologies for some sample resources,
>> and attempt to generalize from there.
>> I'll try to have slideware ready in time for the F2F.
>> Thanks to Michael Hausenblas and David Booth for their help.
>> This email is in the first person because they haven't
>> seen it to agree with it or not, but I am happy to expand
>> "I" to "we" for anything they want to take credit for above.
>> Thanks also to many others including Alan, Tim, Harry Halpin,
>> Stuart Williams, and Noah for their contributions.
>> Jonathan
>> too pressed for time to look up URIs for all the things cited. here
>> are the obscurest ones:
>> memento: http://www.readwriteweb.com/archives/memento_protocol-based_time_travel_for_the_web.php
>> gbif: http://www2.gbif.org/Persistent-Identifiers.pdf
>> iao: http://code.google.com/p/information-artifact-ontology/
>> genont: www.w3.org/DesignIssues/Generic.html
>> the others you should be able to get from google or tracker.
> --
> David Booth, Ph.D.
> Cleveland Clinic (contractor)
> Opinions expressed herein are those of the author and do not necessarily
> reflect those of Cleveland Clinic.
Received on Wednesday, 17 March 2010 20:49:25 UTC

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