Re: RDF-star use cases from Amazon Neptune

On 03/12/2021 12:22, thomas lörtsch wrote:
>
> Am 3. Dezember 2021 11:40:10 MEZ schrieb Pierre-Antoine Champin <pierre-antoine.champin@ercim.eu>:
>> On 03/12/2021 09:23, Dan Brickley wrote:
>>
>>> Yes, nice and concrete!
>>>
>>> What if Alice were Elizabeth Taylor, and Bob were Richard Burton
>> great minds think alike... here is the example I recently proposed for
>> addition in the spec:
>>
>> https://pr-preview.s3.amazonaws.com/w3c/rdf-star/pull/225.html#married-example

>
> You use a new property :occurrence instead of :occurrenceOf in the example before that example. Is there a reason for that?

The most obvious reason is that they have the quoted triple in different 
position (subject/object), so they can't be the same relation. Another 
reason is that I am not at all convinced that, even regardless of the 
direction, these would be the same relation (a long discussion [1] has 
taught me that this was a nasty can of worm).

> Also you use the abbreviated syntax.
Indeed. My point was to show that this is not only possible, but can be 
expressed in a relatively painless way (which is, of course, quite 
subjective).
>   It might be helpful to use the un-abbreviated syntax in all examples except one section where the abbreviated syntax is explained.
I see your point but for me the pros (see above) outweigh the cons.
> Your example does however show that the abbreviated syntax doesn't make anything better w.r.t. the wikidata usecase.
>
> The way wikidata models this is arguably even more horrible.
How can my example "not make it better" if the wikidata model is "more 
horrible"?? :->
>   It is an ordered list with marriages of Richard Burton. Each marriage is a list entry which could be a blank node, etc. Elisabeth Taylor presumably has her own list of marriages and nothing but ardent querying connects the two lists I suppose.
>
>
>> and that was before reading Ora's use-cases... ;)
> The wikidata use case has been part of the RDF* use cases for a year now, or two?
> Of course that classical example has been around for a while... But it
> found it funny that Dan mentioned it just when I integrated it in the
> report. Indulge me.
> Maybe it would be helpful to name this problem properly - not "wikidata usecase" but rather "multiset problem", or "multiset use case"?

what's wrong with "Wikidata usecase"? At least it is explicit...

As for the particular example, I think that "the Taylor-Burton example" 
should do the trick.

   pa

[1] https://github.com/w3c/rdf-star/issues/169

>
>
> Best,
> Thomas
>
>
>>> Wikidata's data model records their two marriages as edge annotations,
>>> on the
>>> https://m.wikidata.org/wiki/Property:P26 relationship linking them.
>>>
>>> Eg. https://m.wikidata.org/wiki/Q34851

>>> https://m.wikidata.org/wiki/Q151973

>>>
>>>  From a Schema.org point of view, being able to express more of what
>>> Wikidata can do seems attractive for interop.
>>>
>>> Dan
>>>
>>> In Burton's entry we have :
>>> spouse
>>>
>>> Elizabeth Taylor
>>> start time 15 March 1964
>>> end time 26 June 1974
>>> series ordinal 2
>>> 1 reference
>>> The Peerage person ID p33443.htm#i334430
>>> retrieved 7 August 2020
>>>
>>> Sybil Christopher
>>> start time 5 February 1949
>>> February 1949
>>> end time 5 December 1963
>>> series ordinal 1
>>> 1 reference
>>> The Peerage person ID p33443.htm#i334430
>>> retrieved 7 August 2020
>>>
>>> Suzy Miller
>>> end time 1982
>>> start time 21 August 1976
>>> series ordinal 4
>>> 0 references
>>>
>>> Elizabeth Taylor
>>> start time 10 October 1975
>>> end time 29 July 1976
>>> series ordinal 3
>>> 0 references
>>>
>>> Sally Burton
>>> start time 3 July 1983
>>> end time 5 August 1984
>>> series ordinal 5
>>> 0 references
>>>
>>>
>>> On Thu, 2 Dec 2021, 21:12 Jos De Roo, <josderoo@gmail.com> wrote:
>>>
>>>      Hi Ora,
>>>
>>>      Very nice use cases and to me it looks quite natural to express
>>>      them as
>>>
>>>      :Bob :isMarriedTo :Alice .
>>>      [] :repr << :Bob :isMarriedTo :Alice >>; :since 2020 ; :source
>>>      :NYTimes .
>>>      [] :repr << :Bob :isMarriedTo :Alice >>; :since 2021 ; :source
>>>      :WashingtonPost .
>>>
>>>      :M1 :pipe :M2 .
>>>      [] :repr << :M1 :pipe :M2 >>; :size "DN 100"; :schedule "30" .
>>>      [] :repr << :M1 :pipe :M2 >>; :size "DN 125"; :schedule "10" .
>>>
>>>
>>>      Kind regards,
>>>      Jos
>>>
>>>      -- https://josd.github.io

>>>      <https://josd.github.io>
>>>
>>>
>>>      On Thu, Dec 2, 2021 at 7:44 PM Lassila, Ora <ora@amazon.com> wrote:
>>>
>>>          Folks,
>>>
>>>          Attached is a document that outlines a couple of uses cases
>>>          (variants of one modeling pattern ,really) we would like to
>>>          submit for consideration by the upcoming RDF-star Working
>>>          Group. I am submitting these now just in case this turns out
>>>          to be relevant to how the charter gets written. Comments are
>>>          welcome, and I am happy to discuss these use cases whenever.
>>>
>>>          Regards,
>>>
>>>          Ora
>>>
>>>          --
>>>
>>>          Dr. Ora Lassila
>>>
>>>          Principal Graph Technologist, Amazon Neptune
>>>
>>>          Amazon Web Services
>>>
>>>          ora@amazon.com
>>>