- From: Mitch Kokar <mkokar@vistology.com>
- Date: Mon, 16 Jul 2007 08:53:38 -0400
- To: "'Giorgos Stoilos'" <gstoil@image.ece.ntua.gr>, "'Ivan Herman'" <ivan@w3.org>
- Cc: <Peter.Vojtas@mff.cuni.cz>, "'Ken Laskey'" <klaskey@mitre.org>, <public-xg-urw3@w3.org>, <mpool@convera.com>
I just wanted to add a few words of clarification to the lively discussion. 1. The URW3 ontology on our web site is in OWL (see http://www.w3.org/2005/Incubator/urw3/wiki/UncertaintyOntology?action=Attach File&do=get&target=Uncertainty.owl). As it is now, it is just OWL-DL. 2. The intent was to have an ontology to annotate use cases, and not to develop a full ontology for reasoning about uncertainty. If we jump into the details, we will loose our focus and will not accomplish our goal. 3. I suggest that we draw the separation line between the annotation of the uncertainty of a sentence and what the sentence is about. Other communities are working on the latter issue, so I suggest we just focus on the former. 4. However, if we want to be at least a little more specific and try to satisfy some of the concerns that Peter has raised, we could add one more property to the ontology, e.g., "includesSentence" whose ___domain and range is Sentence. In that way we could show that a particular sentence is a complex sentence that includes other sentences as components, where those other sentences can have their own uncertainty. If there is support for this, I can make changes in the current URW3 OWL ontology. In summary, although I agree that OWL has (lots of) limitations, I would rather use a language that has formal semantics, rather than trying to propose a new language at this point. This might turn out to be necessary in the future, but for now I hope OWL is sufficient. ==Mitch > -----Original Message----- > From: public-xg-urw3-request@w3.org > [mailto:public-xg-urw3-request@w3.org] On Behalf Of Giorgos Stoilos > Sent: Monday, July 16, 2007 7:55 AM > To: 'Ivan Herman' > Cc: Peter.Vojtas@mff.cuni.cz; 'Ken Laskey'; > public-xg-urw3@w3.org; mpool@convera.com > Subject: RE: [URW3 public] Re: [URW3] ... three questions > based on the last telecon > > > > > > -----Original Message----- > > From: Ivan Herman [mailto:ivan@w3.org] > > Sent: Monday, July 16, 2007 2:33 PM > > To: Giorgos Stoilos > > Cc: Peter.Vojtas@mff.cuni.cz; 'Ken Laskey'; > public-xg-urw3@w3.org; > > mpool@convera.com > > Subject: Re: [URW3 public] Re: [URW3] ... three > questions based on the > > last telecon > > > > > > > > Giorgos Stoilos wrote: > > > Hi Peter, > > > > > > Triples syntax is very specific to the RDF standard > and *not* to > > > every > > W3C > > > standard. For example, triples syntax is not used in OWL (the > > > standard describes a mapping to RDF graphs but a) it > is very limited > > > and cannot capture the OWL Semantics b) other syntaxes are > > > preferred), > > > > ??? why is the mapping limited? > > > > Also: OWL is not equal to OWL-DL. OWL Full is fully > described and > > defined in terms of an extension of RDF semantics, and > the there is a > > very clear mapping between the OWL DL semantics and the > corresponding > > OWL Full semantics. > > > > However: we indeed have to separate two things. There is > a 'syntax', > > essentially RDF/XML, which is nothing more than what it > says: syntax. > > And there is the triple model. Indeed, in some cases > other _syntaxes_ > > are preferred. But that is a secondary issue in my view. > > > > Sorry, I only had OWL DL in mind. So triples syntax (and > not the mapping) is limited in the sense that when mapping > OWL DL to triples one would require to use roles and > concepts in unusual places, like in the subject or object position. > > > > > while > > > RIF > > will > > > not care about triples syntax at all. > > > > > > > This _may_ become correct if you refer to the RDF/XML > syntax. It is > > not correct if you refer to the model of RDF triples. > > Is there going to be a "RIF map to RDF graphs"?. > > -gstoil > > > > > > I think you are mixing two issues here. > > > 1) The specification of an uncertainty ontology, which > describes the > > > concepts and their relations, i.e. the schema, i.e. > the TBox. So I > > > don't > > see > > > why we should add instances (ABox) in the ontology. At > least in my > > > understanding the Ontology is *not* meant to describe > how to capture > > > uncertainty in practice. > > > 2) How to extend ontology languages, like OWL, to add > uncertainty. > > > Then > > we > > > should take into account instances and thus the ABox > and thus your > > example > > > below has a purpose. > > > So I don't understand how reification fits with the Uncertainty > > Ontology. > > > > > > Now, taken that triples are used in RDF (and not in > OWL) I see your > > example > > > below as an effort to extend RDF as to capture > uncertainty, or about > > > serializing an Uncertainty-OWL extension to RDF > triples, which I > > > don't > > see > > > how is relevant. > > > > > > -gstoil > > > > > >> -----Original Message----- > > >> From: public-xg-urw3-request@w3.org [mailto:public-xg-urw3- > > request@w3.org] > > >> On Behalf Of Peter Vojtas > > >> Sent: Monday, July 16, 2007 11:24 AM > > >> To: Ken Laskey > > >> Cc: public-xg-urw3@w3.org; mpool@convera.com > > >> Subject: [URW3 public] Re: [URW3] ... three questions > based on the > > >> last telecon > > >> > > >> > > >> Dear colleaguess (sent to public list and separately > to KL and MP), > > >> > > >> as I have pointed in the ontology page in Top Level > comments by P. > > >> Vojtas is there a mistake?, see > > >> > http://www.w3.org/2005/Incubator/urw3/wiki/is_there_a_mistake%3F > > >> > > >> by W3C standards, basic information unit is a triple > (subject, > > >> predicate, object) which can be true or false in a > structure (to > > >> avoid discussion whether it is a sentence or > proposition, w3c uses > > statement). > > >> > > >> see e.g. http://www.w3.org/TR/rdf-primer/ for > following example > > >> > > >> http://www.example.org/index.html has a creation-date > whose value > > >> is August 16, 1999 > > >> > > >> here we can use reification for another writing asigning an > > >> identifier to the statement > > >> > > >> ex:triple1 rdf:type rdf:Statement > > >> ex:triple1 rdf:subject > http://www.example.org/index.html > > >> ex:triple1 rdf:predicate > > http://purl.org/dc/elements/1.1/creator > > >> ex:triple1 rdf:object > http://www.example.org/staffid/85740 > > >> ex:triple1 ex:creator > http://www.example.org/staffid/85741 > > >> > > >> THIS CONSTRUCTION IS VERY USEFULL IN OUR CASE > > >> > > >> especialy in our ontology discussion the triple > > >> > > >> urw3:Sentence urw3:hasUncertainty urw3:Uncertainty > > >> > > >> should be by my opinion rewritten as > > >> > > >> urw3:triple2 rdf:type rdf:Statement > > >> urw3:triple2 rdf:subject urw3:Sentence > > >> urw3:triple2 rdf:predicate urw3:hasUncertainty > > >> urw3:triple2 rdf:object urw3:Uncertainty > > >> urw3:triple2 ex:creator urw3:Mitch > > >> > > >> and instance ( consider also an "instance" ex:triple1 > > >> urw3:hasUncertainty urw3:0.9) > > >> > > >> as, e.g. > > >> > > >> urw3:triple3 rdf:type rdf:Statement > > >> urw3:triple3 rdf:subject ex:triple1 > > >> urw3:triple3 rdf:predicate urw3:hasUncertainty > > >> urw3:triple3 rdf:object urw3:0.9 > > >> urw3:triple3 ex:creator urw3:Peter > > >> urw3:triple3 urw3:tool urw3:Bayes > > >> > > >> The example with the german sentence (Mathias can > help) is very > > >> usefull (words morgen and Morgen are problematic) > because it shows > > >> what can happen. MP assigns an uncertainty to his own > translation > > >> by expression "if I've translated correctly". > Nevertheless, by my > > >> opinion "Es regnet morgen" is a problematic sentence > because "Es > > >> regnet" is about present and "morgen" with lower case > m in the > > >> begining means tomorrow, it is an adverb. So a > problem accurs, what > > >> to do with a gramaticaly wrong sentence (note that the word > > >> sentence I use here in the linguistical sense, which > in the W3c > > >> terminology can by defined appropriately by > corresponding triples, > > >> by defining predicates like subject, verb, object, > mode (manner), > > >> place and time). I would say either "Es regnet heute > morgen" or "Es wird morgen regnen". > > >> > > >> Sorry for such a long mail, concluding I would like > to say, please > > >> let us use w3c terminology (arguing for necessity of > an extensions > > >> of standards we need be compatible with current > standards). Next, > > >> the > > above > > >> example shows we need to define our own prefix and > rdf vocabulary > > >> for uncertainty ontology. > > >> > > >> Greetings Peter > > >> > > >> > > >> > > >>> *From:* Mike Pool > > >>> *Sent:* Friday, July 13, 2007 3:25 PM > > >>> *To:* public-xg-urw3-request@w3.org > > >>> *Subject:* three questions based on the last telecon. > > >>> > > >>> Hi, all: > > >>> > > >>> We've been having some great discussions during > the meetings > > >>> and > > I'd > > >>> like to pick up a few threads that came up in > the last meeting. I > > >>> reread these as I was trying to write up the minutes: > > >>> > > >>> 1) > > >>> Peter suggested that we use w3c standards as our > guide for the > > >>> meaning of 'proposition'. Peter, do you know if > this is defined > > >>> somewhere by the w3C. Could you point us to the > definition? > > >>> > > >>> 2) > > >>> I argued that propositions, in the sense of the > meaning of a > > >>> sentence that is invariant through all the > paraphrases and > > >>> translations of the sentence, rather than assertions or > > >>> sentences > > as > > >>> the kinds of things that hold probability values. > > >>> > > >>> Kathy noted in the meeting that a problem with > this definition is > > >>> that a system might assign different uncertainty > values to 2 > > >>> different logically equivalent sentences. I > can imagine that > > this > > >>> is possible, but where it occurs I would think > it nothing more > > than > > >>> a weakness in the system, not in the definition > I've suggested. > > For > > >>> example, I might misunderstand 'Es regnet > morgen' as 'it will rain > > >>> this morning' rather than 'it will rain > tomorrow' (if I've > > >>> translated correctly) and assign it a different > probability value > > >>> than that which I'm assigning to 'it will rain > tomorrow'. But I > > >>> think that anyone who observed my doing this > would point out that > > >>> it's a contradiction, i.e., that since these > things have the same > > >>> meaning, I'm obligated to assign them the same > probability value. > > >>> In other words, it is in virtue of their > representing the same > > >>> proposition that I'm obligated to assign them > the same probability > > >>> value. So, I think this only helps to > underscore the fact that > > >>> when we explore our intuitions, we believe that > propositions > > >>> are > > the > > >>> real p.v. holders. > > >>> > > >>> 3) > > >>> Anne, you said at one point that "not all beliefs can > > appropriately > > >>> be represented as numerical values" and that it > "glosses over > > >>> inconsistencies - beliefs may be logically > incompatible". I was > > >>> intrigued by the suggestion, can you say more? > > >>> > > >>> > > >>> Again, thanks all for a stimulating telecon on Wednesday. > > Apologies > > >>> in advance if this address is not the right > forum for these > > >>> discussions. > > >>> > > >>> Best regards, > > >>> > > >>> Mike Pool > > >>> > > >>> -------------------------------- > > >>> > > >>> > > >>> > > >>> > ------------------------------------------------------------------ > > >>> ---- > > -- > > >> ----- > > >>> Ken Laskey > > >>> MITRE Corporation, M/S H305 phone: 703-983-7934 > > >>> 7151 Colshire Drive fax: 703-983-1379 McLean VA 22102-7508 > > >>> > > > > > > > > > > > > > -- > > > > Ivan Herman, W3C Semantic Web Activity Lead > > URL: http://www.w3.org/People/Ivan/ > > PGP Key: http://www.cwi.nl/%7Eivan/AboutMe/pgpkey.html > > FOAF: http://www.ivan-herman.net/foaf.rdf > > >
Received on Monday, 16 July 2007 12:56:08 UTC