pot odds in omaha

[dakevs]

well, i originally started playing NLHE, and have found that i prefer Omaha as a cash game. In hold em, they have the rule of 4/2, where you multiply the # of outs by four on the turn, and do the same on the river, but by two. does it work the same way for calculating pot odds in omaha?

thanks

[jpg7n16]

Yes. It is close enough to the same.

[Ribbo]

[ QUOTE ]
Yes. It is close enough to the same.

[/ QUOTE ]

No, it is nothing like the same.
In Omaha you should never automatically assume that....

1: All your outs are actually outs.
2: You will scoop if you hit.

[jpg7n16]

For the 4/2 rule, I thought both of those conditions are already assumed. (Edited to add: And that's where discounting outs came into play for using the rule)

That rule is a mathematical calculation based on the probabilities of cards coming off. So in NLHE if you determine you have 9 outs (again, this implies that those outs are clean as they may not be against a set), you have roughly 9/47 + 9/46 = 38% about 4*9=36. So it is a rough estimate.

In omaha the percentage is different, but the equity is close enough to the same. Hence my response. Where (since you know 2 more hole cards than holdem) 9/45 + 9/44 = 46.47%, your equity when counting on a flush draw is about 9*4... and that goes down a bit when against a set because your outs are not live.

So here are two situations, first holdem, then omaha. Scenario 1, you have 9 "outs" 9*4=36, so your equity in each scenario should be about 36, which it is:

http://twodimes.net/h/?z=3134926
pokenum -h kc qc - ah ks -- ac 2s 9c
Holdem Hi: 990 enumerated boards containing 2s Ac 9c
cards win %win lose %lose tie %tie EV
Kc Qc 368 37.17 622 62.83 0 0.00 0.372
Ks Ah 622 62.83 368 37.17 0 0.00 0.628

http://twodimes.net/h/?z=3134851
pokenum -o kc qc 3h 8h - ah kh 8s qs -- ac 2s 9c
Omaha Hi: 820 enumerated boards containing 2s Ac 9c
cards win %win lose %lose tie %tie EV
Kc Qc 8h 3h 322 39.27 490 59.76 8 0.98 0.398
Qs 8s Ah Kh 490 59.76 322 39.27 8 0.98 0.602

and then vs a set where your outs aren't as live, against a set, you should discount this flush draw to about 6 outs in both hold'em and omaha - due to the ones that pair the board, so you should have about 6*4=24% equity which you do, as shown below:

http://twodimes.net/h/?z=3134956
pokenum -h kc qc - ah as -- ac 2s 9c
Holdem Hi: 990 enumerated boards containing 2s Ac 9c
cards win %win lose %lose tie %tie EV
Kc Qc 253 25.56 737 74.44 0 0.00 0.256
As Ah 737 74.44 253 25.56 0 0.00 0.744

http://twodimes.net/h/?z=3134894
pokenum -o kc qc 3h 8h - ah as 8s qs -- ac 2s 9c
Omaha Hi: 820 enumerated boards containing 2s Ac 9c
cards win %win lose %lose tie %tie EV
Kc Qc 8h 3h 223 27.20 597 72.80 0 0.00 0.272
As Qs 8s Ah 597 72.80 223 27.20 0 0.00 0.728

In neither game is the rule an exact science, but it is close enough.

[blah_blah]

'double counting' of outs is also a bigger deal in omaha, where it more frequently happens that you hit one of your outs on the turn and then again on the river. For example, say you only have gutshot outs on the flop or backdoor trips outs against top two pair; then you can effectively double the odds of hitting on one street to find the odds of hitting on two streets, since the chances of you hitting your gutshot twice or making backdoor trips are virtually nil. in omaha this doesn't work as well, because we are effectively trying to determine P(A or B) by taking P(A) + P(B) - P(A and B) and saying that P(A and B) is small; it may not be if your draw is very big as frequently happens in omaha.

[Ribbo]

Anyone can come up with theoretical situations to support their case. I can come up with many situations where using that rule is garbage.

Like having a nut flush draw on a Th 7h 4c flop.

The only time it is important to know your outs is when you have your opponents hand defined perfectly. Too many times you think an opponent has something when the reality isn't even close.

Take this first situation:
http://www.pokerhand.org/?1489960
http://www.pokerhand.org/?1485530
Twice I shove a random four cards against two players with aces. I was favourite. But it only takes one of the other two players to think that I am one of the two guys with aces for him to shove something similar, then I inturn believe he has the other aces and shove back.
Then the guy with the actual AA is laughing and we look foolish.

Sometimes a player will call when they clearly don't have odds because they figure they have "implied odds" like this guy did...
http://www.pokerhand.org/?1486571

Sometimes they put you on AA and think that simply by hitting 2 pair they are ahead. (this one is a doozy)
http://www.pokerhand.org/?1485741


Sometimes the two plus two lurkers just like floating you since your "obviously tricky". Good read Perdidle.
http://www.pokerhand.org/?1483453


But the best two hands are probably these:
http://www.pokerhand.org/?1483450
This is a prime example of "counting your outs" in Omaha gone wrong. He calls my raise preflop, hits 3 pair and shoves as a 72/28 dog.
http://www.pokerhand.org/?1483369
This one he shoves as a 2 to 1 dog thinking he is flipping at worst.
You have to be damn certain your outs are actually outs in omaha. Most people end up overplaying because of it.

[darkcore]

these hands contain some very nice examples of mistakes many newb/retarded/inexperienced players in omaha do all the time: they don't assess situations right, are grossly misjudging their odds and outs, can't read hands at all and are doing some rather stupid things.

but where do these hands prove that the rule of is 4/2 wrong?

all the rule says is (in a nutshell) that when a player knows his clean/nut outs (that's what the rule assumes) he can get a rough estimate about the odds to hit his hand.