Re: ontology mapping etiquette (was What is the class of a Named Graph?)

On 02/22/2010 09:44 PM, Richard Cyganiak wrote:
> On 22 Feb 2010, at 19:36, Jiří Procházka wrote:
>>>> I wonder if we as a group of people
>>>> interested in Semantic Web could come up with etiquette for ontology
>>>> mapping.
>>>
>>> Interesting topic! My €0.02: If the other vocabulary is likely to be
>>>
>>> - more stable
>>> - more mature
>>> - more likely to be widely used
>>> - more likely to be around for a longer time
>>>
>>> then you should map your terms to it. If not, don't.
>>>
>>> So IMO the rdfg vocabulary should map to the SPARQL Service Description
>>> vocabulary as soon as it becomes REC, but SPARQL-SD should NOT map to
>>> rdfg.
>>
>> Hi Richard, that also seems reasonable to me at first, but when thinking
>> about it more thoroughly, there is value in both ontologies doing the
>> mapping to the other.
> 
> Yes, if both sides agree, then two-way mappings are great. But this is
> only realistic if both vocabularies rate about equally on the criteria
> above. As an extreme example, it would be totally unrealistic to expect
> the RDFS vocabulary to link back to every vocabulary that has some sort
> of label/name property (all of which should be subproperties of
> rdfs:label).

Yes, I had in mind especially equivalentClass/Property relations and
alike where it doesn't scale much, not subproperties.

> <snip>
>> Certain mapping statements make sense from PoV of one ontology, but not
>> the other.
> 
> I don't know what you mean. An example might help. But anyway, if you
> map to my ontology, but from my POV that mapping doesn't make sense,
> then I'm certainly not going to map back to yours.

I mean when the philosophies of the creators of the ontologies aren't
mutually compatible. I'm unable to come up with some example but just
let's say that someday we will have religious ontologies...

> <snip>
>> If we allow ourselves to go a bit further, I thought it would be great
>> if there was some community developed service which would in automated
>> fashion give advice for improvement and rate user submitted (better yet
>> WoD collected) ontologies judging their quality of design - most
>> importantly re-usability which basically means how is it aligned to
>> other similar ontologies. This would be probably very difficult, at
>> least because of varying opinions on this... I guess database community
>> has something to say about that.
> 
> I think that's a different issue. When it comes to rating the “quality”
> of a vocabulary, then the amount of mappings to other vocabularies is a
> very minor factor. First, because other things (especially amount of
> uptake and strength of the surrounding community) are much more
> important. Second, because adding the mappings is so easy. No vocabulary
> will succeed or fail because of its inclusion or lack of mappings.

Strength of community and amount of uptake matters really a lot, but
next thing you are interested in is how an ontology is compatible with
the rest of your knowledge - how good the mappings are and if it has
mappings to its "competitors", because the they can have mappings to
other ontologies you have not (and how they are good).

> Nevertheless, I agree that we need services that support us in finding
> high-quality vocabularies, and that help drive the improvement of
> existing ones. But it's a complex subject, there are many existing
> efforts (Watson, Talis Schema Cache, Falcons Concept Search,
> ontologydesignpatterns.org, and I probably missed a few), and to me it's
> not obvious what is the right approach.
> 
> Perhaps we don't need better ways of finding and creating vocabularies,
> but better ways of finding and creating communities around a domain that
> can then jointly agree on a vocabulary.

Great point! I would love to see some development in this area...

> All the best,
> Richard
> 
> 
>>
>> There are more things to talk about regarding this, but this is what I
>> have in mind so far.
>>
>> Best,
>> Jiri
>>
>>> Best,
>>> Richard
>>>
>>>
>>>>
>>>> Best,
>>>> Jiri
>>>>
>>>>>
>>>>> Hope that helps.
>>>>>
>>>>> thanks,
>>>>> .greg
>>>>>
>>>>>
>>>>> [1] http://www.w3.org/TR/sparql11-service-description/#id41794
>>>>>
>>>>
>>>
>>
>