:instance vs. :instance-of in guidelines

nschneid commented 8 years ago

@goodmami points out that the guidelines specify that the slash translates to :instance, and shows edges of the form variable —instance→ concept. But elsewhere (e.g., tutorials) we have called this :instance-of, which seems to make sense given the naming conventions on other relations.

goodmami commented 7 years ago

Some potential fallout of changing the direction of this edge is that you can get really ugly AMRs like the following, because concepts are not always terminals:

"Dogs chase dogs"

(c / chase
   :ARG1 (d / (dog :instance d2))
   :ARG2 d2)

Or is there a principled way to prevent this? Maybe an AMR processor would need to know that some -of relations are not to be treated as inverted (cf #194).

nschneid commented 7 years ago

Regardless of whether it's called :instance or :instance-of, I don't see any point in flipping the direction of this edge.

goodmami commented 7 years ago

Sorry, I was mistakenly thinking that if / were :instance instead of :instance-of, the concept would be a leaf in the graph and not re-entrant when the same concept appears more than once, but that is not necessarily true. Also, for context, I'm trying to serialize PENMAN from triples, so it's not so much "flipping" but "choosing" the direction of the edge. Anyway, I think my previous comment is now moot, but thanks for responding.

nschneid commented 6 years ago

Apparently reverted in de7bc91

goodmami commented 6 years ago

@nschneid does that mean there has been a decision about whether / is :instance or :instance-of? Either way is fine with me, I just want to make sure I get it right in my Penman library. Also, if the change gets re-merged, note that the PR did not update the PNG file, so that would need to be done separately.

nschneid commented 6 years ago

I don't know why it was reverted. @amrisi?

uhermjakob commented 6 years ago

I have been updating the guidelines

uhermjakob commented 6 years ago

I have been updating guidelines for the upcoming new AMR release, largely bringing them up-to-date with the AMR corpus, the AMR Dict, and AMR/PropBank frames, which all have evolved.

I am not sure whether we are fully settled on :instance vs. :instance-of. The AMR corpus does not include any explicit :instance of :instance-of; it uses the slash (/).

(c / chase-01
   :ARG0 (d / dog)
   :ARG1 (d2 / dog))

My sense is that the original author (Kevin, I assume) never meant to be prescriptive in that respect. For now, the guidelines stand at:

The slash (/) is shorthand for the instance relation, or, more technically, an :instance-of role. Otherwise, instance is now only mentioned without a preceding colon. :instance-of better follows the precedent of :consist-of, but if we decide to go that route, we should probably interpret it as the inverse of :instance.

But I'm open, as this does not directly affect the AMR corpus in its release form. Any strong feeling regarding :instance vs. :instance-of?

-- Ulf

amrisi / amr-guidelines

:instance vs. :instance-of in guidelines #184