Universal model (was Re: comparing XML and RDF data models)

I'd have to agree that there isn't, and can't be, a universal model
(although, philosophically speaking, I think I'd consider the universe
itself to be the universal model).

What are the implications?
I think* that all this means is that multiple types of models and the
technologies to translate one into another (or reference data in one from
data in another) with both always need to exist.

* - Definitely open to other opinions on this.

Zach

On Wed, Jul 2, 2008 at 7:20 AM, <tim.glover@bt.com> wrote:

>
> Hi Andreas
>
> >>>>>>>>>>>>>
> and what about:
> Person
> +-----------+----------+
> | firstname | lastname |
> +-----------+----------+
> | ...       |          |
> <<<<<<<<<<<<<
>
>
> This is a different *data model*. Every data representation is just a model
> of the world. Nothing can capture the whole of reality. Different models may
> be useful for different things**. No argument there. The alternative XML
> representations are *in addition* to these changes of model.
>
>
> **I just had a thought. I said that there is no universal model, and
> different models are useful for different purposes. Do you agree? If so,
> what are the implications for the semantic web?
>
> Tim.
>
>
> Web of Data Practitioners Days / Oct 22-23 / Vienna
> http://www.webofdata.info
> ----------------------------------------------------------------------
> Dipl.-Ing.(FH) Andreas Langegger
> Institute for Applied Knowledge Processing Johannes Kepler University Linz
> A-4040 Linz, Altenberger Straße 69 http://www.langegger.at
>
>
> On Jul 2, 2008, at 12:25 PM, <tim.glover@bt.com> wrote:
>
> >
> >
> > I think there is a valid observation to be made about XML and RDF or
> > relational representations.
> >
> > Take the simplest atom of information, "There is a Person named John"
> >
> > In RDF, there is only one representation;
> >
> > <Person name John>
> >
> > In RDBMS there is only one representation
> >
> > Person
> > |------|
> > | name |
> > |======|
> > | John |
> > |------|
> >
> > In XML there are several possible representations, eg
> >
> > <Person name="John"/>
> >
> > <Person>
> > <name>John</name>
> > </Person>
> >
> > <Person>
> > <name value="John">
> > </Person>
> >
> >
> > With more complicated data, the possible XML representations vary in
> > different ways, and increase exponentially w.r.t. the number of atoms
> > of information.  To extract the data from the XML we have to know the
> > detailed representation chosen. Saying we can UNION different queries
> > misses the point - we still have to write 3 queries. Saying we can use
> > transformations misses the point - we still have to write
> > transformations.
> >
> > The issue here is that XML fails to abstract the data from the
> > representation as effectively as RDF and RDBMS. In this sense, RDF and
> > RDBMS are better data representations than XML.
> >
> > Tim.
> >
> >
> >
> >
> > -----Original Message-----
> > From: semantic-web-request@w3.org [mailto:semantic-web-request@w3.org]
> > On Behalf Of Bijan Parsia
> > Sent: 02 July 2008 10:29
> > To: Olivier Rossel
> > Cc: semantic-web@w3.org
> > Subject: Re: comparing XML and RDF data models
> >
> >
> > On 2 Jul 2008, at 08:43, Olivier Rossel wrote:
> >
> >>> Any XML instance can be considered a compact, early-bound
> >>> serialization of an infoset RDF graph.
> >>
> >> +1.
> >> XML is very powerful when it comes to presenting data (because it
> >> details how data imbricate with each other). But XML is very
> >> unnatural
> >
> > No, please no. Don't make such claims without backup. What's unnatural
> > for you may be very natural to other people. And naturalness doesn't
> > matter if *effectiveness* is at issue.
> >
> >> when it comes to crawling the data in an unexpected and ever-changing
> >> manner (because XML tree structure is chosen once for all,
> > [snip]
> >
> > And this is just false. Google for "open content model". Look at XML
> > Schema's "lax" and "skip" validation modes. Consider transformations.
> > (I.e., many XML people are perfectly comfortable treating the "input
> > tree" as just one step, not a fixed one)
> >
> > RDF structure is similarly fixed in advanced (by and large).
> >
> > This kind of talk, aside from being wrong, helps marginalize the
> > semantic web and related technologies.
> >
> > In general, if you are inclined to make a general "betterness" claim
> > based on some abstract feature, don't. If you are going to anyway,
> > make sure you have every detail nailed with concrete, preferably real
> > examples ready to hand. Even then, one is better off just presenting
> > the goodness without contrast. If it's good enough, people will come.
> >
> > Cheers,
> > Bijan.
> >
> >
> >
> > -----Original Message-----
> > From: semantic-web-request@w3.org [mailto:semantic-web-request@w3.org]
> > On Behalf Of Bijan Parsia
> > Sent: 02 July 2008 10:29
> > To: Olivier Rossel
> > Cc: semantic-web@w3.org
> > Subject: Re: comparing XML and RDF data models
> >
> >
> > On 2 Jul 2008, at 08:43, Olivier Rossel wrote:
> >
> >>> Any XML instance can be considered a compact, early-bound
> >>> serialization of an infoset RDF graph.
> >>
> >> +1.
> >> XML is very powerful when it comes to presenting data (because it
> >> details how data imbricate with each other). But XML is very
> >> unnatural
> >
> > No, please no. Don't make such claims without backup. What's unnatural
> > for you may be very natural to other people. And naturalness doesn't
> > matter if *effectiveness* is at issue.
> >
> >> when it comes to crawling the data in an unexpected and ever-changing
> >> manner (because XML tree structure is chosen once for all,
> > [snip]
> >
> > And this is just false. Google for "open content model". Look at XML
> > Schema's "lax" and "skip" validation modes. Consider transformations.
> > (I.e., many XML people are perfectly comfortable treating the "input
> > tree" as just one step, not a fixed one)
> >
> > RDF structure is similarly fixed in advanced (by and large).
> >
> > This kind of talk, aside from being wrong, helps marginalize the
> > semantic web and related technologies.
> >
> > In general, if you are inclined to make a general "betterness" claim
> > based on some abstract feature, don't. If you are going to anyway,
> > make sure you have every detail nailed with concrete, preferably real
> > examples ready to hand. Even then, one is better off just presenting
> > the goodness without contrast. If it's good enough, people will come.
> >
> > Cheers,
> > Bijan.
> >
> >
> >
>
>
>
>
>
>
>
>
>
> Web of Data Practitioners Days / Oct 22-23 / Vienna
> http://www.webofdata.info
> ----------------------------------------------------------------------
> Dipl.-Ing.(FH) Andreas Langegger
> Institute for Applied Knowledge Processing Johannes Kepler University Linz
> A-4040 Linz, Altenberger Straße 69 http://www.langegger.at
>
>
>
>
> Web of Data Practitioners Days / Oct 22-23 / Vienna
> http://www.webofdata.info
> ----------------------------------------------------------------------
> Dipl.-Ing.(FH) Andreas Langegger
> Institute for Applied Knowledge Processing Johannes Kepler University Linz
> A-4040 Linz, Altenberger Straße 69 http://www.langegger.at
>
>
>
>
>