Illustration of the data model: a more complex graph?

[iherman]

One of the difficulties in JSON-LD (imho) is that it is difficult to express a more complex graph, namely one that have several "roots" (I know this is not the precise term.). Almost all the examples in the document and elsewhere show the examples where there is one top-level object with an ID and things hang from there (not really a tree, but a bit "tree-like").

We should make it clearer that JSON-LD is capable to do more, in particular in the formal sections, ie, when defining the data model. In practice, Figure 1 should not suggest that the data model is only "tree-like". Alternatively, there should be a Figure 2 showing a different case where it is not the case.

[gkellogg]

I've used "Bush" to describe a graph with multiple start nodes.

And, yes, I think we could add something to 4. Advanced Concepts that elaborates on this use. We do have an example in 4.15 Named Graphs (Example 60) of multiple nodes in the default graph, but it's not explicitly called out and is an odd place to look for it.