is "edge" the same as ROI?

[hypermegachi]

here's the original thread that sparked my interest:
http://forumserver.twoplustwo.com/showfl...part=1&vc=1

no one replied to my question there, so i'll repost it here.
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trying to find things with "edge" through the search is a PITA!

anyways...is this edge for NL cash comparable to the ROI for SnGs/MTTs? both are essentially calculating money in vs money out...

Lyric posted earlier in this thread, where his edge was 1.78% running at 2.2ptbb/100. i don't know if it's actually linear or not, but let's say they are running "good" and have a 3.5% edge running at 5ptbb/100.

that seems awfully low. ROIs for SnGs and MTTs are much higher than that for a good player.

i think my math is wrong...but i don't know why...any ideas?

if i'm correct, then the only reason i see for playing cash over tournaments is you can still make more $/hr. simply because you'd be comparing $100NL to $100 buyins (there aren't very many 1k tournies running, but many ring games).

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[DWarrior]

I don't think the two edges are comparable.

First off, $100NL and $100 SNG/MTT are not the same, I'd guess $50SNGs are about equivalent to $100NL, maybe even $20SNGs. 8-tabling $20 SNGs at 15% ROI, I'm guessing each one takes ~40 mins, you're making about $35-40/hr. $100nl at 4bb/100 will do about the same.

Second, calculationg edge in cash games is very tough, as that Lyric explains. in a $100 SNG you're wagering a set $100. In $100 cash, you can wager anywhere from $10 in one hour to $500. My guess is also that a TAG's edge is higher than a LAG's, because LAG is out there splashing around and getting into marginal situations, where TAGs don't splash nearly as much and are usually bigger favorites when money goes in.

I don't think edge is a very good estimator of your skill or winning ability, bb/100 is the best way for cash.

[AaronBrown]

Both "edge" and "ROI" are defined as expected profit divided by amount at risk. Edge is a casino term, and usually uses the player's amount at risk in the denominator. ROI is always computed from your own point of view.

For example, if a player bets a single number in roulette, she pays $1 for 1 chance in 38 of getting $36. That's an expected loss of $2/38 = 0.0526, so we way there is a house edge of 5.26%. That's dividing by the player's $1. If we divide by the casino's $35 at risk, the casino's ROI is 0.15%.

Both terms are clear when you're discussing a single poker bet. If I put $100 in the pot and increase my EV for the hand by $105, I got a 5% edge or 5% ROI. But it's not so easy to define for a series of bets, and even harder for a session.

If I sit down at a table with $10,000, and walk away with $11,000; I could say I had a 10% ROI on my initial stack, which I put at risk. Or I could take the sum of all my bets, which might be $100,000 or $1,000,000. I don't think either one is very meaningful, I agree with DWarrior.