Subject: Re: [CODE4LIB] Something completely different

From: Peter Schlumpf <[email-masked]>
Date: Wed, 8 Apr 2009 07:25:53 -0500

-----Original Message-----
>From: Alex Osborne <[email-masked]>
>Sent: Apr 8, 2009 4:40 AM
>To: Peter Schlumpf <[email-masked]>
>Cc: [email-masked]
>Subject: Re: [CODE4LIB] Something completely different

>If I'm understanding you correctly, what you have in mind is a
>triplestore.  A database for storing purely relationship triples and
>nothing else.  A triple is made up of the name of an object, the name of
>a type of relationship and a name of another object.  A few example
>abstract triples might be:

Close.  What I have in mind looks more like just pure objects and pointers.  Think in purely abstract terms at this level.  It's possible to have one to many relationships from one object to many other objects.  It would be possible to group sets of objects together by using a single "proxy" object in this database that refers to the others.  But I'm starting to digress.

>> It allows for an interesting extension too -- weighting those
>> associations.  Suppose we use it to create a search structure, and
>> each time we go from one object referencing another we increment a
>> counter for that link by one.
>
>I'm a little confused by this.  What would the use case be?  Are you
>talking about a popularity score for each relationship to weight
>searches with?

Yes, that is one thing I had in mind.  It could be used to analyse browsing behaviour showing what is poular.  Such weights could also decay with time as they get stale.  But this is more an example of an application of the idea rather than something that describes the idea itself.

>Cheers,
>Alex

Thanks for your input,

Peter

---

From: "Dr R. Sanderson" <[email-masked]>
Date: Wed, 8 Apr 2009 13:38:54 +0100

> Close.  What I have in mind looks more like just pure objects and 
>pointers.  Think in purely abstract terms at this level.  It's possible 
>to have one to many relationships from one object to many other 
>objects.  It would be possible to group sets of objects together by 
>using a single "proxy" object in this database that refers to the 
>others.  But I'm starting to digress.

All of which are possible in a TripleStore :)
Or an Object-Relational database, but a triple store would likely find 
more support in the community.

I would encourage looking at rdf triplestores seriously, if the graph 
approach is the direction that you want to go in.

Rob

---

From: Alexander Johannesen <[email-masked]>
Date: Thu, 9 Apr 2009 14:20:10 +1000

> approach is the direction that you want to go in.

Or, Topic Maps which is *not* a triplestore, closer to the OO model
(basically a meta data model), and don't carry the stack "overflow" of
RDF (RDF, RDFs, OWL 1-2-3) nor anonymous nodes. :)

Regards,

Alex
-- 
---------------------------------------------------------------------------
 Project Wrangler, SOA, Information Alchemist, UX, RESTafarian, Topic Maps
------------------------------------------ http://shelter.nu/blog/ --------

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From: stuart yeates <[email-masked]>
Date: Thu, 9 Apr 2009 16:33:24 +1200

> RDF (RDF, RDFs, OWL 1-2-3) nor anonymous nodes. :)

That's not an entirely useful comparison on topic maps and RDF. I suggest:

http://www.ontopia.net/topicmaps/materials/tmrdf.html

We currently use topic maps, alot, in our infrastructure. If we were 
starting again tomorrow, I'd advocate using RDF instead, mainly because 
of the much better tool support and take-up.

cheers
stuart

-- 
Stuart Yeates
http://www.nzetc.org/       New Zealand Electronic Text Centre
http://researcharchive.vuw.ac.nz/     Institutional Repository

---

From: Alexander Johannesen <[email-masked]>
Date: Thu, 9 Apr 2009 14:49:07 +1000

On Thu, Apr 9, 2009 at 14:33, stuart yeates <[email-masked]> wrote:
> That's not an entirely useful comparison on topic maps and RDF.

If I indented to be useful I'd write something substantial, backed up
with stuff other than humour. I'll give that a go the next time. :)

> starting again tomorrow, I'd advocate using RDF instead, mainly because of
> the much better tool support and take-up.

Hmm, not a good thing at all. Could you elaborate, though, as I use it
too as part of infrastructure too, and wouldn't touch RDF / SemWeb
without a long stick? I'm into application semantics and shared
knowledge-bases. What are you guys doing where you feel the support
and tools are lacking? And what are the RDF alternatives?

Regards,

Alex
------------------------------------------ http://shelter.nu/blog/ --------

---

From: stuart yeates <[email-masked]>
Date: Wed, 15 Apr 2009 09:10:19 +1200

> and tools are lacking? And what are the RDF alternatives?

RDF, unlike topic maps, is being used by substantial numbers of people 
who we interact with in the real world and would like to interoperate 
with. If we used RDF rather than topic maps internally, that 
interoperability would be much, much cheaper. It's tempting to say it's 
free, but it's not quite, because it does impose some constraints.

In my eyes, the core thing that RDF supports that topic maps don't seem 
to is seamless reuse by people you don't care about.

For example the people at http://lcsubjects.org have never heard of us 
(that I know of), but we can use their URLs like 
http://lcsubjects.org/subjects/sh90005545#concept to represent our roles.

cheers
stuart

---

From: Alexander Johannesen <[email-masked]>
Date: Wed, 15 Apr 2009 09:40:22 +1000

On Wed, Apr 15, 2009 at 07:10, stuart yeates <[email-masked]> wrote:
> RDF, unlike topic maps, is being used by substantial numbers of people who
> we interact with in the real world and would like to interoperate with. If
> we used RDF rather than topic maps internally, that interoperability would
> be much, much cheaper. It's tempting to say it's free, but it's not quite,
> because it does impose some constraints.

But it's not that hard to create a bridge from RDF to Topic Maps and
back, no? Or is your interop story different?

> In my eyes, the core thing that RDF supports that topic maps don't seem to
> is seamless reuse by people you don't care about.

Yes, this has been brought up on several occasions, including by me at
the TMRA 2008. But then, it's not so much that RDF does something that
Topic Maps doesn't *support*, it's that it's packaged differently. So,
where RDF has got five standard ontology levels (RDF, RDFS, OWL
DL/Lite/Full) Topic Maps got one simpler one (TMDM), yet neither can
express anything  better or differently than the other.

My theory here is that people *like* 5 layers of RDF, because it gives
the false sensation of choice. But it's all ontological definitions.
However, the 5 levels of RDF does indeed create a defined platform for
sharing (if not cast in iron), in which in the TM world you need to
include it / create it.

Oh, and of course the academics seem to have embraced W3C and anything
by the authority of TBL, and its effect is trickling down.

> For example the people at http://lcsubjects.org have never heard of us (that
> I know of), but we can use their URLs like

Not sure I understand your example. Here's my Topic Map identifier in
a Topic Map ;

   http://psi.ontopedia.net/Alexander_Johannesen

Identifier and locator, and resolvable, and can be used by anyone.

Regards,

Alex
------------------------------------------ http://shelter.nu/blog/ --------

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From: stuart yeates <[email-masked]>
Date: Wed, 15 Apr 2009 12:32:31 +1200

> Identifier and locator, and resolvable, and can be used by anyone.

Yes, we mint something very similar (see 
http://authority.nzetc.org/52969/ for mine), but none of our 
interoperability partners do. None of our local libraries, none of our 
local archives and only one of our local museums (by virtue of some work 
we did with them).

All of them publish and most consume some form RDF.

Additionally many of the taxonomies we're interested in are available in 
RDF but not topic maps.

cheers
stuart

---

From: Alexander Johannesen <[email-masked]>
Date: Wed, 15 Apr 2009 10:49:12 +1000

On Wed, Apr 15, 2009 at 10:32, stuart yeates <[email-masked]> wrote:
> Yes, we mint something very similar (see http://authority.nzetc.org/52969/
> for mine), but none of our interoperability partners do. None of our local
> libraries, none of our local archives and only one of our local museums (by
> virtue of some work we did with them).

Hmm, RDF resources are just URIs, so I'm still a bit unsure about what
you mean. Are you talking about the fact that the RDF definitions (and
not the RDF vocabs themselves) aren't encoded in your TM engine?

> Additionally many of the taxonomies we're interested in are available in RDF
> but not topic maps.

Converting them to a Topic Map isn't that hard to do, but I guess
there is *a* cost there.

Regards,

Alex
------------------------------------------ http://shelter.nu/blog/ --------

---

From: stuart yeates <[email-masked]>
Date: Fri, 17 Apr 2009 12:44:19 +1200

> not the RDF vocabs themselves) aren't encoded in your TM engine?

Interoperability isn't just about using the same URL for the same concept.

It's about being able to import each others data for matching (which 
involves having the in-house tools and experience); it's about being 
able to provide mutual support and aid (which involves speaking the same 
language); it's about being part of a community of practise and all that 
that entails.

> Converting them to a Topic Map isn't that hard to do, but I guess

There is little cost in converting it to a topic map, but by using a 
topic map derived from a shared ontology, rather than the shared 
ontology itself, places barriers to interoperability, builds the burden 
of maintenance we need to carry and places us at at least a further step 
from the heart of the community using that ontology.

Given that there are at least four ontologies I'd like to be using, 
multiply that by four.

cheers
stuart