#multigraph

Source details and larger version.

The first published account of the multigraph was in a 1893 issue of an American journal called The Popular Science News.  The journal describes a “curious application to photography” made by “a photographer of Atlantic City, N.J., Mr. Shaw, who produces a photograph at a single exposure which gives five different images of the same person in different positions. This is accomplished by placing the sitter between two mirrors placed at an angle of 45 degrees to each other. The double reflection between these mirrors produces four images of the person placed in front of them, the principle being the same as that of the ordinary kaleidoscope.” It then says that “the result is curious and interesting, and, it has been suggested, would be useful

The mid-part of this Wired article talks a bit about the way Facebook is storing its Open Graph data:

We have an object store, which stores things like users and events and groups and photos, and then we have an edge store that stores the relationship between objects. With Open Graph, we built a layer on top of those systems that allowed developers to define what their objects look like and what their edges look like and then publish those third party objects and edges into the same infrastructure that we used to store all of the first party objects and edges.

Couple of thoughts:

this data is a good example of a multigraph

I don’t think Facebook is actually using a graph database for storing the data. Considering the size of the data Facebook is handling, this could be understandable

There’s no mention of how the metadata, the description of the objects and edges, is stored. I assume this should somehow be connected to historical data to allow the evolution of the data while maintaining its original meaning over time.

The processing happening on this multigraph data sounds like cluster analysis