Re: [OEP,ALL] Potential topics for OEP notes

Chris, Alan, OEP-ers,

What is the target audience for our notes? I know that we don't have 
any practical way of answering this question, but we have to make an 
educated guess. My guess is as good as anyone's, but my feeling is that 
there are a lot more people looking for notes on very simple stuff 
rather than something large and more complicated, as many things in 
Chris's list are. Of course it's much more interesting for _us_ to 
write notes on non-trivial stuff, but I am not sure we'll be getting 
more people on board with these. If people are struggling with getting 
even very simple things right in developing their ontologies (as many 
on the protege-owl list are, for instance), they won't be very much 
interested in many different types of part-of or an ontology of time. 
And these are the people who we probably need to help if we want to 
have the critical mass of content on the SW.

Of course, having all the notes that Chris has suggested would be good, 
but I am not sure many of them take higher priority than some simpler 
ones:

- Numeric ranges -- really, really need this one!
- Closing axioms -- without that, classifiers would seldom produce 
anything useful and if anyone wants to promote the DL abilities of OWL 
(admittedly, I am not one of those people :), you need to tell people 
how to get even simple things work. Alan has tons of these, in addition 
to closing axioms
- Simple note on units and measures. This came up at one of the recent 
telecons: suppose I have an ontology on units (presented in a different 
WG note or just something I have), how do I represent the fact that 
John's height is 6 feet (and 180 cm) in OWL? I think this is different 
from the note that Chris was referring to.
- Part of -- I am all for producing a simple version of partOf that 
Evan suggested first.

These are all much more light-weight (and less fun to write :) than the 
ones Chris suggested. It doesn't have to be either/or, but we'll 
probably have to set some priorities, given the limited resources that 
we have.
	
Natasha

On Oct 11, 2004, at 1:13 AM, Alan Rector wrote:

>  Chris, All
>
>  Can I add something like -
>
>  a) options for using Ontologies in applications - whether in OWL or 
> RDF - this is the thing the SWBP  really has to crack. Picking up 
> where Classes as Values left off.  I am not sure where pointers to 
> specific tricks with current technology fit in, but in the 
> "deployment" part of SWBP&D I think many people would welcome a list 
> of tool combinations that were known to work, however time limited 
> that list will inevitably be.  I am certainly not in a position to 
> produce such a list; I don't think the list per se is really part of 
> OEP, but we need someplace where we coordinate the principles the 
> notes with practice..
>
>  b) When to use a reasoner and normalisation.
>
>  c) I am not sure whether it is a note, but it is worth pointing 
> people at 'common pitfalls'. One contribution towards that is
>  
>
>  Other comments below...
>  
>  
>
>  Christopher Welty wrote:
>   
>  ...
> The partOf relation.  There really isn't that much that can be "said" 
> in OWL (and therefore less in RDF) regarding the typical 
> axiomatizations of partOf, but knowing the different kinds of partOf 
> relations and what they are supposed to mean would be useful.  I'm 
> hoping that some subset of Nicola, Alan, and I can take the lead on 
> this one, but I also see the need for a couple of notes here, so I 
> think this needs further discussion.  For example Deborah expressed 
> interest in a simpler note (less ambitious but quicker turnaround) on 
> geographical containment.
>  I am happy to take a major role in this, but not until after 6 Dec 
> (ISWC plus a major week-long teaching stint - some of which will 
> include material on partonomy.)  I shall also be writing a paper on 
> the topic or probably two.
>
>  On the other hand, partonomy is a big topic.   The trick is to keep 
> it simple for the simple cases. I suggest that we need at least two 
> kinds of notes or note fragments.
>
>  1)    Notes laying out the classic distinctions, pointing to the the 
> literature on merology, and pointing out things like that most users 
> of partonomy probably want something that is time specific - X is a 
> part of Y at some implied time T (the type is a part of the car now, 
> but it may not be after the tyre has been changed) - or normative (Xs 
> are considered parts of Ys).  You need one or the other to avoid 
> getting into issues about amputated fingers, cat's tails, etc.  Also I 
> think we have to say that this area is far from settled so we are 
> giving guidance on workable principles plus caveats for controversies.
>
>  2)    Implementation mechanisms. Transitive properties for simple 
> things. SEP triples are related trickse..
>
>      RegionOfFrance = France or restriction(is_geographical_region_of 
> someValuesFrom(France))]
>
>  property hierarchies showing different relations between containment, 
> location and partonomy.
>
>  3) Also warnings that with current classifiers (possibly excepting 
> FaCT++ but we aren't sure yet) large ontologies containing extensive 
> networks linked by both has_part and is_part_of (or any other 
> transitive relation and its inverse) are potentially combinatorially 
> explosive.  If anybody does try to use a classifier it is 
> disconcerting to see what seemed to work for a toy run indefinitely 
> for something real.
>  
>  
>   
>
>  Units and measures.  There has been some work on this, including in 
> Cyc, Tom Gruber's ontology in Ontolingua, and Helena Sofia-Pinto did a 
> nice one for the old SUO effort.  Evan was interested in this and it 
> certainly makes sense to have someone at NIST do it.
>
> Subjects.  The notion of what a subject "is" and what the "subjectOf" 
> relation means can be quite confusing.  I have done a lot of work on 
> this and am willing to take this one on, however I will want to do one 
> at a time.
>
> Time.  Jerry Hobbs has done a very thorough job putting together a 
> consensus ontology of time based on a lot of existing time ontologies, 
> most of which draw from the Allen calculus.  The ontology is expressed 
> in FOL (KIF), but there are (necessarily simplified) DAML+OIL and OWL 
> ("OWL-Time") versions  available.  Jerry has expressed interest in 
> seeing this as a W3C note.
>  I'd be very interested in seeing this.
>   
>
>  Fluents.  Closely tied to the notion of time is being able to say 
> that a binary property "holds" for a time. e.g. one may want to say 
> that "Chris is a member of the W3C from Sept, 2004 - Sept 2005".  A 
> property like memberOf is a fluent because it can be said to hold at a 
> time (this is not strictly a correct definition, but it will 
> suffice).  While OWL-Time let's you represent a time interval like 
> "Sept, 2004-Sept, 2005", it remains neutral wrt what happens at or 
> during such a time interval.  The typical move in FOL is to use a 
> function or add an argument to the predicate, e.g. memberOf(Chris, 
> W3C, time-interval-1), however clearly we can't do that in OWL or RDF, 
> since we are limited to binary predicates.  One solution is to go for 
> full reification of fluents, as in the exsiting not on n-ary 
> relations, however there are some other choices.  I'm hoping I can get 
> Pat Hayes and Richard Fikes to work with me on this one.
>  An important distinction for the medical community is whether it is 
> the fluent that is reified or the observation of the fluent, i.e. 
> whether we have
>
>  (X as observed by O at time T) is_member_of Group or
>
>    X is_member_of (Group at time T)
>
>  The first is the way to describe a log book of observations such as 
> the medical record; the second is probably more important for models 
> of language phenomena such as the classic "The King of France".
>
>  The other alternative which fits closely with some indexed notions of 
> parthood such as barry Smith's, is
>
>     X (is_member_of at_time t) Group.
>
>  but that involves reifying 'is_member_of'
>   
>
>  On the side of "ontology engineering":
>
> Ontology 101 tutorial specifically for OWL/RDF.
>  I'd hope that some of the pizza tutorial material could get into 
> this, or perhaps beside it.
> There is an interesting comparison - I am not sure it is for a best 
> practice note - that the pizzas and wines require different paradigms, 
> or at least different emphasis.  Pizzas are primarily about 
> construction - pizzas have someValuesFrom topping.  Wines are 
> primarily about exclusion - CarbernetSavignon is made only 
> (allValuesFrom) CarbernetSauvignonGrapes.
>   
>
>  I think a note to help orient people on the role OWL and RDF in 
> semantic integration is critical, I get pinged on that regularly.  I 
> lot of people think OWL is the silver bullet for semantic integration 
> (I suggested at ISWC last year that semantic integration is a 
> mountain, not a werewolf, and OWL is, at best, a small silver chisel). 
> There was just a Dagstuhl symposium on this subject in general (i.e. 
> not specific to OWL), and special issues of AI Magazine and Sigmod 
> record coming out as well.  I hope Natasha and/or MikeU will take the 
> lead on such a note.
>  
>
>  People who know what "ontology" and "semantics" actually mean (in the 
> much larger world outside of computer science), often ask why the two 
> have become nearly synonymous on the semantic web.  Personally, I 
> think its a fair question and a short note on why we're so confused 
> would be worthwhile.  Maybe this goes in another task force (wasn't 
> there a clean up the mess we've made task force?)
>
> We're open to other suggestions.
>
> -Chris (OEP co-co)
>
> Dr. Christopher A. Welty, Knowledge Structures Group
> IBM Watson Research Center, 19 Skyline Dr., Hawthorne, NY  10532     
> USA
> Voice: +1 914.784.7055,  IBM T/L: 863.7055, Fax: +1 914.784.7455
> Email: welty@watson.ibm.com, Web: 
> http://www.research.ibm.com/people/w/welty/
>
> -- 
> Alan L Rector
> Professor of Medical Informatics
> Department of Computer Science
> University of Manchester
> Manchester M13 9PL, UK
> TEL: +44-161-275-6188/6149/7183
>  FAX: +44-161-275-6236/6204
> Room: 2.88a, Kilburn Building
> email: rector@cs.man.ac.uk
>  web: www.cs.man.ac.uk/mig
>          www.opengalen.org
>          www.clinical-escience.org
>          www.co-ode.org
>  

Received on Monday, 11 October 2004 20:37:25 UTC