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Re: question on primer example

From: Pascal Hitzler <pascal.hitzler@wright.edu>
Date: Wed, 03 Oct 2012 14:07:03 -0400
To: Sebastian Rudolph <rudolph@kit.edu>
Cc: "Polleres, Axel" <axel.polleres@siemens.com>, "public-owl-comments@w3.org" <public-owl-comments@w3.org>
Message-id: <506C7EC7.1080903@wright.edu>
 > Well, put into model theoretic terms
 > (1) the "some" version requires all models to satisfy that every
 > teenager must have an age (and furthermore this age must be in a certain
 > range), whereas
 > (2) the "all" version allows for models that have teenagers who do not
 > have any age associated to them, because the "all" axiom would not be
 > violated by ageless teenagers.
 > To me, variant (1) seems to be more appropriate.

+1

Certainly, adding functionality makes sense. But then the goal here was 
not to make a complete ontology, but to exemplify the constructs.

Best Regards,

Pascal.


On 10/3/2012 12:04 PM, Sebastian Rudolph wrote:
> Hi Axel,
>
>>
>> Hi Sebastian,
>>
>>> As far as your suggestion to use "all" instead of "some" is
>>> concerned, this would not convey the intended semantics since
>>> then all individuals which are *not* in a hasAge relation to
>>> any value would be classified as teenagers (mind the somewhat
>>> unintuitive interpretation of the "all").
>>
>> Why? If you refer to the last example in
>> http://www.w3.org/TR/2009/REC-owl2-primer-20091027/#Advanced_Use_of_Datatypes
>> "Teenager" is declared as a *subclass* of those with some (or as I
>> suggest 'all') ages between 13 and 19.
>
> Very good point. In my answer I was assuming the classes had been
> specified as equivalent (which would probably be more adequate).
> I still advocate the "some" in the current modeling but I have to modify
> my argument a little.
>
>> In the "all" reading, all I could infer is IMO that someone with an
>> age out of that range would be inferred *not* to be a
>> Teenager (which I find quite intuitive, but which wouldn't work for
>> the "some" reading), right?
> It *would* work for the "some" reading if "hasAge" is specified to be
> functional according to the following reasoning:
> xyz hasAge 55 =(hasAge is functional)=> xyz has not any Age other than
> 55 => xyz has not any Age between 13 and 19 => xyz is not a Teenager
>
> Indeed, it would not work without the functionality axiom.
>
>> So, I don't really get it (maybe an embarrassing, temporary
>> brain-malfunctioning :-) but happy to learn where my mistake is).
>>
>>> (mind the somewhat
>>> unintuitive interpretation of the "all").
>>
>> Can you elaborate?
> Well, put into model theoretic terms
> (1) the "some" version requires all models to satisfy that every
> teenager must have an age (and furthermore this age must be in a certain
> range), whereas
> (2) the "all" version allows for models that have teenagers who do not
> have any age associated to them, because the "all" axiom would not be
> violated by ageless teenagers.
> To me, variant (1) seems to be more appropriate.
>
> Best regards,
>    Sebastian
>
>
>>
>> (BTW, I am happy to take this discussion to another, more
>> adequate list, if this is not the right place, as mentioned
>> earlier, this is not intended as a formal comment to the spec)
>>
>> Axel
>>
>>> -----Original Message-----
>>> From: Sebastian Rudolph [mailto:rudolph@kit.edu]
>>> Sent: Mittwoch, 03. Oktober 2012 12:01
>>> To: Polleres, Axel
>>> Cc: public-owl-comments@w3.org <mailto:public-owl-comments@w3.org>
>>> Subject: Re: question on primer example
>>>
>>> Hi Axel,
>>>
>>> it might be better to refer to the current version of the
>>> primer, i.e. http://www.w3.org/TR/2009/REC-owl2-primer-20091027/
>>> If you take the mentioned snippet per se, you are right, it
>>> allows for persons having more than one age. However if you
>>> also specify the axiom
>>>
>>> FunctionalDataProperty( :hasAge )
>>>
>>> it defines :hasAge to be functional and hence allows only one
>>> age per individual. If you assume this axiom, then the
>>> definition of Teenager via "some" is perfectly fine.
>>> As far as your suggestion to use "all" instead of "some" is
>>> concerned, this would not convey the intended semantics since
>>> then all individuals which are *not* in a hasAge relation to
>>> any value would be classified as teenagers (mind the somewhat
>>> unintuitive interpretation of the "all").
>>>
>>> Best,
>>> Sebastian
>>>
>>>
>>>
>>>
>>>
>>> Am 03.10.2012 um 09:19 schrieb Polleres, Axel:
>>>
>>>> Hi,
>>>>
>>>> I have some question on the primer example on DataRanges, cf.
>>>> http://www.w3.org/TR/2008/WD-owl2-primer-20080411/#Adatarange
>>>>
>>>> The prose text says
>>>> "For example, we might have Teenager as those people whose
>>> age is an integer that is at least 13 but less than 20, Adult
>>> as those people whose age is at least 21, and Child as those
>>> people whose age is in the complement of adult ages."
>>>>
>>>> Class: Teenager EquivalentClass: Person and hasAge some
>>> integer[>= 13
>>>> , < 20]
>>>> Class: Adult EquivalentClass: Person and hasAge some integer[>= 21]
>>>> Class: Child EquivalentClass: Person and not ( hasAge some
>>> integer[>=
>>>> 21] )
>>>>
>>>> As it stands, this seems to allow several ages per person -
>>> one of which is in the defined range.
>>>> IMO, it would be more intuitive to use for the first two
>>> lines "all" instead of "some" here plus stating that age is
>>> functional (each person has exactly one age, wouldn't it?
>>>>
>>>> Not a big deal nor meant as a formal comment, but just to
>>> note and ask for some opinion from the group or explanation
>>> why you got to formulate the example like that.
>>>>
>>>> With best regards,
>>>> Axel Polleres
>>>>
>>>> Siemens Aktiengesellschaft Oesterreich CT RTC BAM CON-AT
>>>> Siemensstrasse 90 1210 Vienna, Austria
>>>> Tel.: +43 51707-36983
>>>> Mobile: +43 664 88550859
>>>> mailto:axel.polleres@siemens.com
>>>>
>>>> Company Name: Siemens Aktiengesellschaft Oesterreich; Legal Form:
>>>> Stock Corporation; Company Seat: Vienna; Register Number:
>>> FN 60562 m;
>>>> Registered at: Commercial Court Vienna; DVR-Number: 0001708
>>>
>>> _________________________________________________
>>> PD Dr. Sebastian Rudolph
>>> senior researcher & project leader at AIFB Karlsruhe
>>> Institute of Technology (KIT)
>>> rudolph@kit.edu <mailto:rudolph@kit.edu>                    phone +49
>>> 721 608 - 47362
>>> www.sebastian-rudolph.de <http://www.sebastian-rudolph.de>        fax
>>> +49 721 608 - 45998
>>>
>>>
>
> _________________________________________________
> PD Dr. Sebastian Rudolph
> senior researcher & project leader at AIFB
> Karlsruhe Institute of Technology (KIT)
> rudolph@kit.edu <mailto:rudolph@kit.edu>                    phone +49
> 721 608 - 47362
> www.sebastian-rudolph.de <http://www.sebastian-rudolph.de>        fax
> +49 721 608 - 45998
>

-- 
Prof. Dr. Pascal Hitzler
Kno.e.sis Center, Wright State University, Dayton, OH
pascal@pascal-hitzler.de   http://www.knoesis.org/pascal/
Semantic Web Textbook: http://www.semantic-web-book.org
Semantic Web Journal: http://www.semantic-web-journal.net
Received on Wednesday, 3 October 2012 18:07:31 GMT

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