[iccrg] Pareto frontier

Michael Welzl <michawe@ifi.uio.no> Wed, 08 January 2020 13:52 UTC

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From: Michael Welzl <michawe@ifi.uio.no>
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Subject: [iccrg] Pareto frontier
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Hi,

Recently, it has become common in some congestion control papers, when showing plots with various congestion control mechanisms and a "better" arrow, to also draw a line through the presumably best mechanisms and call it a Pareto frontier.

I find it a bit of a stretch to just call this line a Pareto frontier - it MAY be one, but that's not proven, so I'm not sure this is a correct thing to state, strictly speaking. Anyway, I've recently seen cases where mechanism XY beats the others, as shown in the diagram, where it "sits comfortably outside the Pareto frontier".

Now, either I totally misunderstand something, or I never got the idea of Pareto efficiency, OR such a statement is utter nonsense.
(because being better than the mechanisms on the Pareto frontier simply means that this line is indeed *NOT* the Pareto frontier, and it was wrong to call it that in the first place).

Can someone enlighten me please?

Cheers,
Michael