Re: OWL Full Features in QRG

I wasn't trying to be difficult -- I was trying to make QRG better  
and hence more widely usable. Anyway, I agree that this is a  
relatively minor issue and I won't say any more about it.

Ian


On 27 May 2009, at 00:51, Jim Hendler wrote:

> Jie has suggested adding 4 lines to the document, not a major  
> section - this would still be quick, but would be important to the  
> OWL/RDF community who need to know some terms are not being used  
> anymore - I think that group also wants/need QUICK -- if you are  
> worried about size, we could always go back to the version that  
> didn't include the structural syntax :-)  Seriously, this document  
> serves a number of purposes, and JIe's very small addition of  
> section 4.2 seems not to get in the way and to be needed by the  
> constituencies we care about --- JH
>
> On May 25, 2009, at 6:11 AM, Ian Horrocks wrote:
>
>> Jie,
>>
>> You still seem to labour under the misapprehension that the goal  
>> of QRG is to provide a *comprehensive* reference. On the contrary,  
>> the goal is to provide a *QUICK* reference (the name gives a hint  
>> on this).
>>
>> There will always be some tension between speed and  
>> comprehensiveness. In almost all useful examples of quick  
>> references that I have seen/used comprehensiveness is deliberately  
>> sacrificed in favour of ease of use. The target audience is people  
>> who are not very familiar with the language and who often need to  
>> remind themselves of its syntax. Such people typically won't use  
>> the more esoteric parts of the language -- they just need an easy  
>> to use cheat-sheet covering the most commonly used features.  
>> Remember when you were first learning a language? Your tool of  
>> choice was no doubt some relatively short list of common words --  
>> not the 20 volume OED.
>>
>> Ian
>>
>>
>>
>> On 22 May 2009, at 18:20, Jie Bao wrote:
>>
>>> On Fri, May 22, 2009 at 5:13 AM, Ian Horrocks
>>> <ian.horrocks@comlab.ox.ac.uk> wrote:
>>>> I must say that I am in full agreement with Bijan here -- adding
>>>> distinguishing marks would be going backwards.
>>>>
>>> Same Here
>>>
>>>> To be honest, I am baffled by the notion that deprecated  
>>>> vocabulary should
>>>> occur in the QRG *at all*. The main target audience of QRG is  
>>>> surely people
>>>> creating OWL 2 documents who need a quick reminder of the syntax  
>>>> of the the
>>>> construction they are trying to use. Offering them the  
>>>> possibility to use
>>>> deprecated vocabulary is *not* useful.
>>>>
>>> Before considering adding those vocabulary, I also thought they are
>>> "deprecated". However, I was warned that only owl:DataRange is
>>> officially deprecated [1]. For owl:DeprecatedClass and
>>> owl:DeprecatedProperty, there have been quite a lot of discussion  
>>> that
>>> they are *not* deprecated [5]; this is similar to  
>>> owl:distinctMembers
>>> (but I don't find the record).
>>>
>>> For owl:OntologyProperty, since a lot of discussion was pre-date my
>>> joining to the WG, I'm not sure about its status, but from the  
>>> record
>>> of Issue-91 [3] and the lack of an official vote on its  
>>> deprecation, I
>>> believe it should not be treated as a deprecated vocabulary either.
>>> Issue-91 actually was solved with action 82 "Edit the  
>>> specification to
>>> mention the well-known ontology properties in the spirit of OWL  
>>> 1.0",
>>> I don't remember when this was changed to completely remove  
>>> "ontology
>>> property" from the structural definition (and other user-facing
>>> documents) and only mention it in the RDF semantics.
>>>
>>> There have been argument on what is deprecation of XXX, e.g. [2]
>>> defines it to be
>>> - no mapping rule from the functional syntax to XXX is given
>>> - a mapping rule the other way is specified
>>>
>>> However, as far as I know, the WG has never come to the conclusion
>>> that this is an official definition of deprecation, and have came  
>>> to a
>>> formal vote on the list of deprecated vocabulary.
>>>
>>> [1] http://www.w3.org/2007/OWL/tracker/issues/29 Issue 29  
>>> (owl:DataRange)
>>> [2] http://lists.w3.org/Archives/Public/public-owl-wg/2008Jan/ 
>>> 0163.html
>>> Jeremy Carroll on the definition of "deprecation"
>>> [3] http://www.w3.org/2007/OWL/tracker/issues/91
>>> [4] http://www.w3.org/2007/OWL/tracker/actions/82
>>> [5] http://www.w3.org/2007/OWL/tracker/issues/90
>>>
>>>> Finally, with this kind of card it is definitely the case that  
>>>> "less is
>>>> more". Adding irrelevant or obscure material to the card will  
>>>> make it harder
>>>> to use and eventually useless.
>>>>
>>> That's true in general (and that's why I gave up adding a few other
>>> RDF vocabulary), but I wonder if the 5 terms mentioned in the  
>>> section
>>> meet this criteria: they have been a part of the OWL 1  
>>> vocabulary, are
>>> not officially deprecated except for owl:DataRange, and are  
>>> supported
>>> by all existing OWL tools which means many ontologies produced from
>>> these tools will still use them, even for years to come. And since
>>> they are still OWL 2 Full features, they are actually relevant  
>>> part of
>>> the languages thus may deserve some proper documentation in QRG.
>>>
>>> Jie
>>>
>>>> Ian
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> On 21 May 2009, at 21:48, Bijan Parsia wrote:
>>>>
>>>>> On 21 May 2009, at 20:36, Jie Bao wrote:
>>>>>
>>>>>> On Wed, May 20, 2009 at 4:21 PM, Michael Schneider  
>>>>>> <schneid@fzi.de>
>>>>>> wrote:
>>>>>
>>>>> [snip]
>>>>>>>
>>>>>>> Well, since I am asked...
>>>>>>>
>>>>>>> What would I expect from such a card (I admit that I did not  
>>>>>>> ponder much
>>>>>>> about QRG in the past)? Thinking more generally, what I would  
>>>>>>> expect
>>>>>>> from
>>>>>>> other languages (a card for HTML for example), yes, I think  
>>>>>>> as long as
>>>>>>> it is
>>>>>>> technically possible (enough space on the card), I would want  
>>>>>>> to have
>>>>>>> /all/
>>>>>>> language features mentioned on it, even if they are "rarely  
>>>>>>> used",
>>>>>>> "legacy"
>>>>>>> or even "deprecated".
>>>>>>
>>>>>> I agree
>>>>>
>>>>> Frankly, neither of you are reasonable members of the target  
>>>>> audience.
>>>>>
>>>>> It also seems like Michael at least just hasn't used such  
>>>>> cards. I'm not
>>>>> sure how useful it is to engage in imaginings at this point.
>>>>>
>>>>>>> Because it is quite possible that I want to / have to use  
>>>>>>> this card when
>>>>>>> working with old ontologies.
>>>>>
>>>>> You never have to use the card. And if you are using old  
>>>>> ontologies I
>>>>> would recommend using a card for that language.
>>>>>
>>>>> Even in the ideal case, I think having extra cruft is a problem  
>>>>> (since
>>>>> it's typically a distraction). But when you are trading off  
>>>>> things like font
>>>>> size, etc. it's really silly.
>>>>>
>>>>>>> I wouldn't really want to have the "special"
>>>>>>> features in a separate section, but rather along with the  
>>>>>>> other features
>>>>>>> belonging to the same category. But I would appreciate if  
>>>>>>> there were a
>>>>>>> *small* marker placed nearby a feature telling what's special  
>>>>>>> with them.
>>>>>
>>>>> Michael, perhaps you forgot the length discussion in the  
>>>>> telecon why even
>>>>> a small "new" is bad design. Here's why: Distinguishing marks  
>>>>> *draw the eye*
>>>>> and *attract the attention* (this is a well known principle of  
>>>>> design).
>>>>> Using it to draw people who are trying to use the language  
>>>>> (period) is to
>>>>> *mislead* the and make the card significantly more confusing.
>>>>>
>>>>> This same principle applies to outlier or deprecated features.  
>>>>> The *last*
>>>>> thing you want is to draw people's attention to them, esp. that of
>>>>> relatively naive users.
>>>>>
>>>>> Note that this attention drawing affect works even on  
>>>>> sophisticated users
>>>>> (as eye tracking studies can show). So it hits *everyone*.
>>>>>
>>>>>>> For
>>>>>>> example, if a term is deprecated, I would consider this relevant
>>>>>>> knowledge
>>>>>>> for my work, e.g., even if I were required to leave the old  
>>>>>>> term in the
>>>>>>> ontology for the moment, I won't add additional occurrences,  
>>>>>>> and could
>>>>>>> plan
>>>>>>> for a future redesign.
>>>>>
>>>>> This is such a specialized situation as to be really quite  
>>>>> irrelevant for
>>>>> the design of a QRG. If you want to produce such a card for  
>>>>> that situation,
>>>>> go ahead. Even then, I would suggest *not* including it in the  
>>>>> "main"
>>>>> working card, and producing a *separate* card for things you  
>>>>> should avoid.
>>>>>
>>>>> [snip]
>>>>>
>>>>>>> Such a card is good for learning by doing: One looks  
>>>>>>> something up once
>>>>>>> or
>>>>>>> twice when one stumbles over it, and afterwards one knows  
>>>>>>> about it and
>>>>>>> its
>>>>>>> special aspects, but still have the helpful card around, if  
>>>>>>> one forgets
>>>>>>> about it again. But then it would be un-helpful if some terms  
>>>>>>> were not
>>>>>>> mentioned in the card.
>>>>>>>
>>>>>> Agreed
>>>>>
>>>>> We should not be designing for outlier situations. You can  
>>>>> always cook up
>>>>> a scenario where having this or that would be possible useful.  
>>>>> But you have
>>>>> to evaluate the total costs as well.
>>>>>
>>>>>>> So to summarize: I would keep the terms in, and even along  
>>>>>>> with the
>>>>>>> other
>>>>>>> terms (no separate section), but with some marker ("D" =  
>>>>>>> "deprecated"
>>>>>>> for
>>>>>>> DataRange, "L" = "legacy" for most others, perhaps really "R" =
>>>>>>> "RDF-Based
>>>>>>> Semantics" for OntologyProperty (not clear on this)).
>>>>>>>
>>>>>> Seen discussion above. The proposed markers, there are also  
>>>>>> problems:
>>>>>> for "L" - if a term is not officially deprecated, its status  
>>>>>> is not
>>>>>> really "legacy" in a formal way; for "R" - the problem is  
>>>>>> ontology
>>>>>> properties are treated as annotation properties in OWL 2 DL,  
>>>>>> that's
>>>>>> they are not purely only available in RDF-based semantics.
>>>>>
>>>>> [snip]
>>>>>
>>>>> I consider this in all likelihood to damage the overall utility  
>>>>> and
>>>>> usefuless of the card.
>>>>>
>>>>> Why on earth are we going here? I mean, truly, what *is* the  
>>>>> motivation?
>>>>> This in principle can only but rarely useful and ever more  
>>>>> rarely useful
>>>>> over time. Why go there?
>>>>>
>>>>> Cheers,
>>>>> Bijan.
>>>>>
>>>>
>>>>
>>>
>>>
>>>
>>> -- 
>>> Jie Bao
>>> http://www.cs.rpi.edu/~baojie
>>
>>
>
> "Con un poco de semántica ya se consigue ir muy lejos"
>
> Prof James Hendler				http://www.cs.rpi.edu/~hendler, @jahendler,  
> twitter
> Tetherless World Constellation Chair
> Computer Science Dept
> Rensselaer Polytechnic Institute, Troy NY 12180
>
>
>
>
>
>

Received on Wednesday, 27 May 2009 07:45:26 UTC