I still think this is an important point, and I’ve been thinking there should be a bloggy write-up of the maths in this area on LW/AF! Maybe you (or I, or Jacek, or Charlie, or Joar, or whoever...) could make that happen.
The original EPIC definition, and the STARC defs, can be satisfied while yielding only a pseudometric on the quotient space. But they also include many full (quotient) metrics, and the (kinda default?) L2 choice (assuming full-support weighting) yields a full metric.
You’re right. For some reason, I thought EPIC was a pseudometric on the quotient space and not on the full reward space.
I think this makes the thing I’m saying much less useful.
I still think this is an important point, and I’ve been thinking there should be a bloggy write-up of the maths in this area on LW/AF! Maybe you (or I, or Jacek, or Charlie, or Joar, or whoever...) could make that happen.
The original EPIC definition, and the STARC defs, can be satisfied while yielding only a pseudometric on the quotient space. But they also include many full (quotient) metrics, and the (kinda default?) L2 choice (assuming full-support weighting) yields a full metric.