Re: Slides for Berlin Data Workshop

Update the presentation to distinguish “blank nodes” from “blank node identifiers” along with the following provision:

Note that blank nodes may be identified with a blank node identifier, which people seem to hate. However, the notion that some nodes in a graph don’t have an explicit name shouldn’t be too controversial. By definition these are blank nodes.

Gregg Kellogg
gregg@greggkellogg.net

> On Feb 24, 2019, at 1:07 PM, Gregg Kellogg <gregg@greggkellogg.net> wrote:
> 
>> On Feb 24, 2019, at 7:56 AM, Pierre-Antoine Champin <pierre-antoine.champin@univ-lyon1.fr <mailto:pierre-antoine.champin@univ-lyon1.fr>> wrote:
>> 
>> Dear Gregg,
>> 
>> this is very nice.
>> 
>> Slide 5, you might want to mark your JSON-LD example as "not working yet' (AFAIK, the @univar type is not part of the standard, right?)
> 
> Thanks, yes, it’s totally hypothetical; it may not be sufficient, e.g., for values of `@id`.
> 
>> Also, a lot of people are allergic to blank nodes (and some of them even have quite valid arguments...). Proposing to put *more* blank nodes as soon as slide 2 might antagonize those people, who may become less receptive to the remaining of the presentation. Maybe it would be a good idea to forestall this, with a slide between 1 and 2, or may be just an oral warnin, in the line of:
>> 
>> " I know that blank nodes can be painful to cope with, but there are solutions: skolemization, correctly defining their scope, etc... Under this premise, I don't consider blank nodes to be taboo.”
> 
> Good point; IMHO, the probably isn’t so much with blank nodes as explicit blank node identifiers (_:bn001). Blank nodes are simply nodes in a graph without a name. The examples don’t actually use blank node identifiers, so “blank nodes” is probably more accurate anyway. In fact, most use in schema.org <http://schema.org/> of Microdata or JSON-LD is without explicit node names.
> 
> Gregg
> 
>> best
>> 
>> On Sat, 23 Feb 2019 at 23:51, Gregg Kellogg <gregg@greggkellogg.net <mailto:gregg@greggkellogg.net>> wrote:
>> The format for the Berlin Data Workshop [1] remains unclear, but I’ve prepared just a couple of slides to describe one way in which Anonymous Named Graphs in JSON-LD could support the property graph use case.
>> 
>> > https://json-ld.org/presentations/JSON-LD-Support-for-Property-Graphs/ <https://json-ld.org/presentations/JSON-LD-Support-for-Property-Graphs/> <https://json-ld.org/presentations/JSON-LD-Support-for-Property-Graphs/ <https://json-ld.org/presentations/JSON-LD-Support-for-Property-Graphs/>>
>> 
>> 
>> There’s a short overview of new things in JSON-LD 1.1, and as a bonus, a sketch of how Notation3 reasoning might look in JSON-LD. (Hint, we really only need to invent a way to describe universal variables at the syntax level; reasoning should be universal based on obvious projections from Notation 3. The required extensions to RDF Datasets and better description of reasoning semantics are work to be done elsewhere).
>> 
>> Gregg Kellogg
>> gregg@greggkellogg.net <mailto:gregg@greggkellogg.net>
>> 
>> 
>> [1] https://www.w3.org/Data/events/data-ws-2019/schedule.html <https://www.w3.org/Data/events/data-ws-2019/schedule.html>
>> 
>> 
>