[topicmapmail] Wiki/WebLog application built on top of topicmaps...

[Guy Murphy]

Well, one way link is managed, and visible from its point of origin.... it's
worth consideration because it's simpler than having to think about how
you're going to manage the filtering of a two-way link when you're only
interested in the assertion from one side.

Using an associative datamodel we wouldn't even be having this conversation.

I might assert "Guy Murphy" == "friend" ==> "Meg Ryan" ... and there's
nothing useful to say about Megs role in this rlationship other than she's
the subject of the assertion -- which importantly is implicit already in the
assertion -- because she doesn't even know of my existence. Nor is she
likely to want to manage my assertion.

It's nice to be able to express richly the roles of all participants
involved in a relationship, but quite often there's nothing more useful to
say than one participant is merely the subject or the assertion... at such
times being forced to create a meaningful assertion the other way creates
noise not any useful information.... and that I think is an important flaw
with topicmaps... noise.... I find they have a tendency to be noisy, and
being able to indicate a direction to an association would be one way of
helping to cut down that noise, especially with one-to-many relationships
where the information is quiet and useful on one side, and noisy and dilute
on the other side.

Now with an associative model, with links going one way, one has the option
of asserting a link in the other direction... one can implement a topicmap
ontop of the associative model... you have more options available to you as
a data modeller not fewer.

As for managing relationships which are one way... you manage them from the
side making the assertion... which is the whole point, as the other side
isn't interested in even seeing them, nevemind managing them.

Cheers,
    Guy.

----- Original Message -----
From: "Anthony B. Coates" <abcoates@TheOffice.net>
To: "Guy Murphy" <guy.murphy@easynet.co.uk>; <topicmapmail@infoloom.com>
Sent: Wednesday, January 15, 2003 12:16 PM
Subject: Re: [topicmapmail] Wiki/WebLog application built on top of
topicmaps...


> ** Reply to message from "Guy Murphy" <guy.murphy@easynet.co.uk> on Wed,
15 Jan
> 2003 11:54:49 -0000
>
> Dear Guy,
>
> > While what you suggest will filter the links it wont really filter them
in
> > any manner that changing one participants role from "topic" to
"blind-topic"
> > wont, and it adds and extra association to manage... and that's the crux
of
> > the issue... with your suggestion the user would still be left with a
couple
> > of hundred "hidden-because-user-is-not-interested" associations to
manage,
> > and I'm still going to be left hiding those associations as a special
case
> > and left deciding how to manage them as a special case.
>
> You are completely right that roles are the key to understanding the
> directionality (in both directions) of topic map associations, and there
is no
> reason why "blind-topic" could not be a subclass of "topic".  However, I
don't
> understand how omni-directional associations make the management any
easier at
> all.  They still exist in the system, so someone still has to manage them,
and
> presumably the user cannot, so the ball is left in your court.  If you
hide
> uninteresting bi-directional links from the user, then they cannot manage
them,
> and the ball is equally in your court.  I really cannot see a difference
in
> practical terms.
>
> Cheers,
> Tony.
> ====
> Anthony B. Coates, Information & Software Architect
> mailto:abcoates@TheOffice.net
> MDDL Editor (Market Data Definition Language)
> http://www.mddl.org/
> FpML AWG Member (Financial Products Markup Language)
> http://www.fpml.org/
>