Re: WebOnt General Requirements Subgroup - Initial E-mail

Pat Hayes wrote:
> 
> >Deborah,
> >
> >Thanks, your arguments have convinced me. In fact, I now think the
> >multi-user issues and difference and merging are closely related to
> >requirements I had listed.
> >
> >Everyone, I think it would be helpful if we can try to identify how the
> >various candidate requirements (original list from Jim, Deborah's list,
> >my list) are related. Here is my first cut at such a mapping:
> >
> >Jeff's                 Deborah's               Original list
> >-------------------    --------------------    -------------------
> >shared meaning         multi-user
> >ontology reuse         extensible
> >ontology evolution     versioning              versioning
> >interoperability       diff and merge          domain mapping
> >inconsistency                                  inconsistency
> >scalability            scalability             large ontologies
> >user-friendly          ease of use
> >data persistence
> >                       security
> >                       XML interfaces
> >                       internationalization
> >                                               ontology-based search
> >                                               ontology querying
> >
> >Although this table only shows Deborah's "multiple users" requirement
> >mapped to my "shared meaning" requirement, I think it also maps to my
> >"ontology reuse" and "ontology evolution" requirements.
> >
> >Everyone, I'd like you to look at this table and decide if you agree
> >with my mappings.

That's a lot of stuff. Do I agree that "security" 
is a requirement? er... in some form, yes, of course.

I have a couple/three suggestions:

(1) make sure the requirements are testable.

how do you do that?

(2) make sure the requirements are connected to
use cases, so that if we don't meet requirement R6,
it's clear that we won't be able to deal
with use cases UC4 and UC7, say.

and how do we do all that with so little time?

(3) shoot for the intersection of everybody's requirements,
not the union. Shoot for things that *the group*
will agree are requirements; i.e. things that
if our language doesn't meet them, the group will
agree that we're not done.


If we end up with things that seem important
but aren't really agreed as requirements, I'd
suggest listing them as goals or something.


Coming back from the meta-discussion...

About inconsistency... I'm happy with
a requirement that our language should
(a) have the ability to express
inconsistent facts (e.g. using disjoint)
and (b) the specification should have
clear semantics for what's an inconsistency
and what's not, but I don't want to
go as far as (c) that it be straightforward, computationally,
to determine, given any two expressions
in our language, whether they're consistent.

i.e. the sort of use cases I have in mind
for a requirement about inconsistencies
are, for example, catching common
ontology-design errors (flag empty
classes, flag empty classes that have
things in them ;-), or well-known
errors in the use of some ontology,
like perhaps units mismatches in
a space-ship-parts ontology.

But I don't have any use cases that
motivate a general decidability requirement.


-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/

Received on Monday, 10 December 2001 16:21:49 UTC