How to model multiple conferences and different presenters of single topic?

[senged]

Requested advice/help on modeling a scenario involving multiple conferences, presentations, and people presenters.

Scenario

There are multiple unique events of a conference under the same umbrella (unique instances of the same conference event class if you will). There is a common superset of presentations, with different subsets selected for each conference. Importantly, the author will not always present the topic at each conference.

The following diagram represents the situation without the needed presenter intersection:

Options

To be honest I'm really struggling on ideas here, hence this post request for help.

Using the guidance of nodes as entities/things, and relationships as verbs, what is the best way to describe this in words? Person 'Alice' presents presentation 'Topic B' at conference 'Cx Earth'?

I found this graphgist (Exploring A Conference), but it doesn't cover my scenarios of multiple events and presenters, I suspect because the node 'Presentation' seems to cover both the event of the presentation slot and the presentation material. I'm looking to keep common the presentation content across events.

Intersection Node?

Given the word version above, to me this implies an intersection of the three nodes Alice, Topic B, Cx Earth. Is this a common/accepted modeling practice in graphs? Or ... is this really meaning this intersection is the presentation event unique from the presentation content?

Thanks in advance for any advice.
-Ed

[pingelsan · Accepted solution]

This is a very common pattern in modeling events. Some agent (presenter) does something (talk) with some tool or material (presentation content) at a certain place and time (conference event). This is slightly (but only slightly) counterintuitive because one could expect the actual presentation to be the 'relationship' between presenter and conference, but as soon as three or more entities are involved, an additional node is required.
The Music Ontology for example defines events to model individual instances of some performer to play a certain instrument at a given time/place... Just for comparison: http://motools.sourceforge.net/event/event.html

Best regards,
Christoph

[senged]

@pingelsan Thanks very much for the confirmation and description, and amazingly fast response!! It was helpful for me to write it down, but being a novice it is extremely valuable to get some feedback and have people to communicate with. I will pursue this path.