Re: [External] : Re: use of multi-valued rdf:reifies removes ability to annotate individual triple-patterns

The point is that this is something that affects all attempts to represent 
information.

peter


On 4/15/24 00:15, Souripriya Das wrote:
> [There was a copy/paste typo in my example: It should have had => :f2 
> rdf:reifies <<( :s3 :p3 :o3 )>> .]
> 
> Hi Peter,
> 
> Yes, because your example too involves a multi-valued property, if we think of 
> the inverse property :sourceOf.
> 
> So, my point is that, as shown in my examples, using rdf:reifies in a 
> multi-valued manner may lead to the need to change the data significantly (if 
> the need for annotation of individual triple-terms arises later). That would 
> involve query rewriting as well. So, modeling using multi-valued rdf:reifies 
> could a bit risky.
> 
> Thanks,
> Souri.
> 
> ------------------------------------------------------------------------------
> *From:* Peter F. Patel-Schneider <pfpschneider@gmail.com>
> *Sent:* Sunday, April 14, 2024 5:17 PM
> *To:* public-rdf-star-wg@w3.org <public-rdf-star-wg@w3.org>
> *Subject:* [External] : Re: use of multi-valued rdf:reifies removes ability to 
> annotate individual triple-patterns
> This modelling issue is not specific to :reifies.
> 
> Consider
> 
> :a :source :x .
> :b :source :x .
> :x :publication "NYT" .
> 
> This says that :a and :b have the same :source, whatever that means.  If you
> later want to add more information about :source, for example :year, then you
> can't put different :years for this :source.   You have to either have the
> same :year or make a change to something like:
> 
> :a :source :x .
> :b :source :y .
> :x :publication "NYT" .
> :x :year 2023 .
> :y :publication "NYT" .
> :y :year 2022.
> 
> This says that :a and :b have the same value for the :date.
> 
> peter
> 
> 
> On 4/14/24 14:37, Souripriya Das wrote:
>> A shortcoming of using multi-valued rdf:reifies is that you lose the ability 
>> to add statements about the individual triple-terms. I have tried illustrating 
>> this with the following simple examples.
>> 
>> Example 1: using multi-valued rdf:reifies
>> =========
>> :e rdf:reifies <<( :s1 :p1 :o1 )>>, <<( :s2 :p2 :o2 )>> ; :source :src1 ; 
>> :year 2023 .
>> :f rdf:reifies <<( :s1 :p1 :o1 )>>, <<( :s3 :p3 :o3 )>> ; :source :src2 ; 
>> :year 2024 .
>> 
>> What if we want to indicate that the <<(: s1 :p1 :o1 )>> triple-term in :e has 
>> a different :month annotation than the one in :f? The following does not help 
>> because we cannot specify that the one in :e is associated with :g and the one 
>> in :f is associated with :h.
>> 
>> :g rdf:reifies <<( :s1 :p1 :o1 )>> ; :month 5 .
>> :h rdf:reifies <<( :s1 :p1 :o1 )>> ; :month  12 .
>> 
>> Example 2: using single-valued rdf:reifies, along with rdfs:member (or some 
>> similar) property
>> =========
>> 
>> :e1 rdf:reifies <<( :s1 :p1 :o1 )>> .
>> :e2 rdf:reifies <<( :s2 :p2 :o2 )>> .
>> :e rdfs:member :e1, :e2 ; :source :src1 ; :year 2023 .
>> 
>> :f1 rdf:reifies <<( :s1 :p1 :o1 )>> .
>> :f2 rdf:reifies <<( :s2 :p2 :o2 )>> .
>> :f rdfs:member :f1, :f2 ; :source :src2 ; :year 2024 .
>> 
>> This is a multi-level structure that, although more verbose, allows 
>> annotations at each level. So, the following achieves the objective.
>> 
>> :e1 :month 5 .
>> :f1 :month 12 .
>> 
>> The second approach – using single-valued rdf:reifies and rdfs:member – 
>>   allows one to use a uniform way to create multi-level structures (e.g., a 
>> document with levels: chapter -> section-> paragraph -> sentence).
>> 
>> Thanks,
>> Souri.
>> 
>> 
>> 
>> 
> 

Received on Monday, 15 April 2024 10:53:25 UTC