Does ROI directly translate to edge over opposition?

[Myst]

Assuming that the average player, by defintion, has a -9.09% ROI, then does a player with a 10% positive ROI have a 19.09% edge over his compeition?

[Angelic_Ace]

Maybe if those ROI's were taken from 1000+ tournies at the same level, and if these two guys played a few hundred tournies against each other. In one tourney it doesn't guarantee any sort of percentage edge. It might mean you're overall a much more solid player though.

[HesseJam]

I think it means that your edge against the average field is 19% which illustrates that the 9% rake is scary, doesn't it?

OTH, the rake in the .5/1.0 limit full ring is about 4.5 BB/100 and it is way harder to have a 4.5BB/100 (= 9BB/100 edge) winrate there. So, it is harder to match the poker room profit in full ring than in SnGs.