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RE: Learning from other disciplines?

From: Booth, David (HP Software - Boston) <dbooth@hp.com>
Date: Thu, 26 Feb 2009 17:03:29 +0000
To: Alan Ruttenberg <alanruttenberg@gmail.com>
CC: Michael Hausenblas <michael.hausenblas@deri.org>, Jonathan Rees <jar@creativecommons.org>, AWWSW TF <public-awwsw@w3.org>
Message-ID: <CD2B872281385A439B98164F5351E6DD416FC92037@GVW1144EXB.americas.hpqcorp.net>
> From: Alan Ruttenberg [mailto:alanruttenberg@gmail.com] 
> 
> 2009/2/26 Booth, David (HP Software - Boston) <dbooth@hp.com>:
> > Hi Alan,
> >
> >> From: Alan Ruttenberg [mailto:alanruttenberg@gmail.com]
> >>
> >> The AKT example in that note seems to me to be in the 
> wrong direction.
> >> The problem is that there is no theory of what AKT is. Here is a
> >> theory: AKT is some class of proteins, instances of which are
> >> individual protein molecules. Later it is discovered that there are
> >> various subclasses (no surprises - any class can have 
> subclasses, and
> >> even AKT, before the "splitting" could be considered to have
> >> subclasses - for instance those that were phosphorylated).
> >> When these subclasses are discovered, one adds ... subclass axioms.
> >> AKT1 subclassOf AKT.
> >
> > Yes, it is true that in the scenario described, if AKT had 
> > been modeled as a class rather than as an instance, the 
> > relationship between AKT and AKT1, AKT2 and AKT3 could have 
> > been expressed merely as a subclass relationship.  That is an 
> > important point.  But the point of this scenario is not to 
> > debate whether Jann *should* have modeled AKT as a class or 
> > an individual.  The point is that, as long as individuals are 
> > used, they will sometimes be ambiguous (at least to some 
> > applications -- they may be precise enough for others), and 
> > in such cases we need a way to deal with it without breaking 
> > existing applications.
> 
> This is where we disagree. I don't think we should be spending our
> time teaching people hacky workarounds for poor modeling. We need to
> spend our time having people think clearly about modeling in the first
> place.
> 
> Otherwise we land up with a same as historical mess of incommensurate
> data dressed up in a brand new syntax.

While I certainly agree that good modeling practice should *also* be taught, and it *will* help in averting *some* of this kind of problem, this is not *merely* a problem of poor modeling.  This kind of problem will not go away no matter how good people get at modeling.

The decision of whether to model something as a class or as an individual is a design trade-off that has significant practical implications.  Different applications will -- quite reasonably -- weigh those trade-offs differently and make different choices.  The essential problem is that a model that is reasonable and practical for one application may not be usable -- at least not directly -- by another application that has more sophisticated needs.  This is not about good or bad modeling, it is about different application needs.

For example, modeling the earth as flat is perfectly fine for an application that just needs to compute driving directions around town -- indeed, taking into account the curvature of the earth would be wasteful overkill -- though of course such a simplistic model would be completely inadequate for an application that needs to compute satellite locations.  One might claim that modeling the earth as flat was *wrong*, and the designers should have modeled it differently.  But it is pointless to do so, because that *is* the most reasonable and efficient way to model it for the driving applications being addressed.  

The point is that regardless of how good we get at modeling, we will still have ambiguity, so we need to accept that reality and learn how to cope with it.  (See Pat Hayes's In Defense of Ambiguity
http://www.ibiblio.org/hhalpin/irw2006/presentations/HayesSlides.pdf )
And it turns out that the perennial httpRange-14/IR-versus-non-IR issue can be viewed as just another instance of this kind of ambiguity problem.


David Booth, Ph.D.
HP Software
+1 617 629 8881 office  |  dbooth@hp.com
http://www.hp.com/go/software

Statements made herein represent the views of the author and do not necessarily represent the official views of HP unless explicitly so stated.

> 
> -Alan
> 
> >
> > I've updated the scenario to make this clearer:
> > [[
> > It is worth noting that in this particular scenario, the 
> problem that Jann and Luke face could have been averted if 
> they had initially modeled these genes as classes rather than 
> as individuals, because then AKT1, AKT2 and AKT3 could simply 
> have been subclasses of AKT.  Indeed, modeling things as 
> classes does help avert -- or at least postpone -- this kind 
> of issue, though it may create other issues.  However, the 
> point of this scenario is not to debate Jann's modeling 
> decisions, it is to illustrate how this ambiguity issue can 
> be addressed when it does arise.  Thus, we need to assume 
> that, for whatever reason, Jann did what he did, and Katie's 
> application then depended on Jann's definitions.
> > ]]
> >
> >>
> >> Separately one has terminology. The word "AKT" was initially only a
> >> label for AKT. Later it also became a label for AKT1. No surprise
> >> again - words are notoriously ambiguous.
> >
> > Yes, that happened historically, but it is irrelevant to 
> the point of the AKT scenario I described.  I've clarified 
> the note at the beginning to indicate more clearly that the 
> scenario I describe was merely *inspired* by the history of 
> AKT, but the details are fictional: "This scenario was 
> inspired from the actual history of AKT.  However, the names 
> and other details are completely fictional."
> >
> >>
> >> There is no need to introduce these *completely undefined* 
> relations
> >> s:isBroaderThan etc. There *is* a need to understand and 
> use existing
> >> *defined* mechanisms, such as rdfs:subClassOf and 
> rdfs:label, in this
> >> case.
> >>
> >> rdfs:comment wouldn't be a bad idea while we're at it.
> >
> > I don't understand why you say that these are undefined.  
> They are defined in a later section of the document, as 
> noted, using rdf:comment:
> > http://dbooth.org/2007/splitting/#isBroaderThan
> > [[
> > s:isBroaderThan a rdfs:Property ;
> >    rdf:label "isBroaderThan" ;
> >    rdf:comment """s:isBroaderThan indicates that the subject URI
> >        has a URI declaration that is broader than some URI 
> declaration
> >        of the object URI.  (See s:isBroaderThanDeclaration.)
> >        This is a convenience property:
> >        Since a URI could have more than one URI declaration,
> >        this property makes weaker statements than
> >        s:isBroaderThanDeclaration. """ ;
> >    rdfs:domain xsd:anyURI ;
> >    rdfs:range xsd:anyURI .
> >
> > s:isNarrowerThan a rdfs:Property ;
> >    rdf:label "narrows" ;
> >    rdf:comment """isNarrowerThan is the inverse of 
> s:isBroaderThan.""" ;
> >    rdfs:domain xsd:anyURI ;
> >    rdfs:range xsd:anyURI .
> > ]]
> >
> > Did you want some other kind of definition?
> >
> >
> >
> > David Booth, Ph.D.
> > HP Software
> > +1 617 629 8881 office  |  dbooth@hp.com
> > http://www.hp.com/go/software
> >
> > Statements made herein represent the views of the author 
> and do not necessarily represent the official views of HP 
> unless explicitly so stated.
> >
> >
> >>
> >> -Alan
> >>
> >> On Thu, Feb 26, 2009 at 4:39 PM, Michael Hausenblas
> >> <michael.hausenblas@deri.org> wrote:
> >> >
> >> > Thanks David!
> >> >
> >> > Re http://dbooth.org/2007/splitting/ - yes, I'm aware of it
> >> (actually
> >> > bookmarked it on delicious on 26 Jan 2009 ;) and of course
> >> I read it.
> >> >
> >> > I must admit that when I read your note I didn't really
> >> get/see this point.
> >> > My bad, sorry.
> >> >
> >> > @Jonathan: as there are at least two people around that
> >> think into the same
> >> > direction and maybe some more that could imagine this can
> >> solve some of our
> >> > issues around httpRange, IR, etc. - how about adding it to
> >> the TAG F2F
> >> > agenda? Or is it too late? Too vague?
> >> >
> >> > Cheers,
> >> >      Michael
> >> >
> >> > --
> >> > Dr. Michael Hausenblas
> >> > DERI - Digital Enterprise Research Institute
> >> > National University of Ireland, Lower Dangan,
> >> > Galway, Ireland, Europe
> >> > Tel. +353 91 495730
> >> > http://sw-app.org/about.html
> >> > http://webofdata.wordpress.com/
> >> >
> >> >
> >> >> From: "Booth, David (HP Software - Boston)" <dbooth@hp.com>
> >> >> Date: Tue, 24 Feb 2009 22:06:53 +0000
> >> >> To: Michael Hausenblas <michael.hausenblas@deri.org>, AWWSW TF
> >> >> <public-awwsw@w3.org>
> >> >> Subject: RE: Learning from other disciplines?
> >> >>
> >> >> Michael,
> >> >>
> >> >> That sounds similar what I've been arguing for quite a while:
> >> >>
> >> >>  (a) Ambiguity is unavoidable. (Pat Hayes has articulated
> >> this point much
> >> >> better than me though.)
> >> >>
> >> >>  (b) The ambiguity involved in failing to distinguish
> >> between an IR and a
> >> >> non-IR is not fundamentally different than other kinds of
> >> ambiguity.
> >> >>
> >> >>  (c) Something that is adequately clear and unambiguous to
> >> one application may
> >> >> be ambiguous to another application, because different
> >> apps have different
> >> >> needs.  A URI such as http://markbaker.ca/ that denotes
> >> both a person and a
> >> >> web page may be perfectly fine for an application that has
> >> no need to
> >> >> distinguish between IRs and non-IRs, but it may cause
> >> confusion and havok to
> >> >> an application that relies on such a distinction.
> >> >>
> >> >>  (d) Therefore, there is no need to view such
> >> IR-versus-non-IR ambiguity as a
> >> >> violation of web architecture, though it may be a
> >> violation of good practice.
> >> >>
> >> >> These points are explained a but further in
> >> >> http://dbooth.org/2007/splitting/#httpRange-14
> >> >>
> >> >>
> >> >>
> >> >> David Booth, Ph.D.
> >> >> HP Software
> >> >> +1 617 629 8881 office  |  dbooth@hp.com
> >> >> http://www.hp.com/go/software
> >> >>
> >> >> Statements made herein represent the views of the 
> author and do not
> >> >> necessarily represent the official views of HP unless
> >> explicitly so stated.
> >> >>
> >> >>
> >> >>> -----Original Message-----
> >> >>> From: public-awwsw-request@w3.org
> >> >>> [mailto:public-awwsw-request@w3.org] On Behalf Of Michael
> >> Hausenblas
> >> >>> Sent: Tuesday, February 24, 2009 8:39 AM
> >> >>> To: AWWSW TF
> >> >>> Subject: Learning from other disciplines?
> >> >>>
> >> >>>
> >> >>> All,
> >> >>>
> >> >>> This is a crazy idea, but please give it a thought before
> >> >>> rejecting it ...
> >> >>>
> >> >>> As far as I gather 'we' sort of fail to agree if we
> >> >>> should/can define IR and
> >> >>> non-IR or even if we need to differentiate between documents
> >> >>> and abstract
> >> >>> things at all. One could now try to understand the problem
> >> >>> from a totally
> >> >>> different point of view by learning from quantum mechanics.
> >> >>>
> >> >>> You are surely aware of the waveparticle duality [1]? So why
> >> >>> can't we try
> >> >>> to apply the same idea here. We can say, for example,
> >> that for a given
> >> >>> application/use case the distinction between IR and non-IR
> >> >>> makes no sense at
> >> >>> all and hence is useless; all that counts at the end of the
> >> >>> day are some
> >> >>> bytes and maybe some metadata that we can get over the wire.
> >> >>> In other cases
> >> >>> one thing may be abstract or one thing may be a document. The
> >> >>> Web version of
> >> >>> the 'waveparticle duality'-equivalent would then 
> render sort of:
> >> >>>
> >> >>> ===
> >> >>> The 'document-thing duality' addresses the inadequacy of
> >> >>> classical concepts
> >> >>> (from the operating system domain, software development,
> >> etc.) like
> >> >>> "document" and "abstract thing" in fully describing the
> >> behaviour of
> >> >>> Web-scale objects.
> >> >>> ===
> >> >>>
> >> >>> Comments, anyone?
> >> >>>
> >> >>> Cheers,
> >> >>>       Michael
> >> >>>
> >> >>> [1] http://en.wikipedia.org/wiki/Wave-particle_duality
> >> >>>
> >> >>> PS: Jonathan, thanks a lot for your detailed comments re the
> >> >>> dependencies
> >> >>> visualisation - I will address them in a separate mail (esp.
> >> >>> the n^2 table
> >> >>> approach - I like it ;)
> >> >>>
> >> >>> --
> >> >>> Dr. Michael Hausenblas
> >> >>> DERI - Digital Enterprise Research Institute
> >> >>> National University of Ireland, Lower Dangan,
> >> >>> Galway, Ireland, Europe
> >> >>> Tel. +353 91 495730
> >> >>> http://sw-app.org/about.html
> >> >>> http://webofdata.wordpress.com/
> >> >>>
> >> >>>
> >> >>>
> >> >
> >> >
> >> >
> >>
> 
Received on Thursday, 26 February 2009 17:05:10 UTC

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