betting a flush draw

[Thythe]

Many consider this a +EV move, and I'm sure it can be, but I was wondering why it is so +EV. Is it only +EV if you are willing to bet out again if you don't make the flush?

[Homer]

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Many consider this a +EV move, and I'm sure it can be, but I was wondering why it is so +EV. Is it only +EV if you are willing to bet out again if you don't make the flush?

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What sort of situation are you talking about?

1) Semi-bluffing:

One limper, SB completes, you check your option with 6 /images/graemlins/spade.gif 4 /images/graemlins/spade.gif. The flop comes A /images/graemlins/spade.gif 7 /images/graemlins/spade.gif 2 /images/graemlins/diamond.gif. SB checks, you bet...

2) Pumping for value:

Four limpers, you call in CO with A /images/graemlins/heart.gif 2 /images/graemlins/heart.gif, blinds complete/check. Flop comes 8 /images/graemlins/heart.gif 7 /images/graemlins/heart.gif 3 /images/graemlins/club.gif. SB bets, all call, you raise...

3) Something else?

-- Homer

[Thythe]

Hmmm, I guess either situation. I've never thoroughly thought about either (certainly about time I do). I think I mean more for the first situation, though. In the second situation you are betting with the pot odds as you have so many callers. For the first situation to be profitable, though, do you need to be willing to raise the turn even if you miss your flush?

[Homer]

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Hmmm, I guess either situation. I've never thoroughly thought about either (certainly about time I do). I think I mean more for the first situation, though. In the second situation you are betting with the pot odds as you have so many callers.

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It's not about pot odds, actually. The size of the pot is only important for determining whether or not you should call/chase. Whether or not you should pump has to do with the number of opponents you are up against. With the nut flush draw, you are 2:1 against getting there by the river, so if you are up against 3 or more opponents, you are making money on each additional bet that goes into the pot.

Examples:

- You flop the nut flush draw, there is no money in the pot and the SB bets. There are 4 callers before the action gets to you. You should raise because you're getting 5:1 (I don't know if there is a term for this -- call it "betting odds") on each additional bet that goes into the pot and are only 2:1 against making your hand by the river.

- You flop the nut flush draw, there are 1,000,000 bets in the pot and your only opponent bets into you. You shouldn't raise (assuming you can't steal and have no additional outs), since you're only getting 1:1 on each additional bet that goes into the pot and are 2:1 against getting there. You should call, however, since you're getting pot odds of 1,000,000:1.

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For the first situation to be profitable, though, do you need to be willing to raise the turn even if you miss your flush?

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I believe you will get both opponents to fold more than 1/4 of the time, so betting the flop will be immediately profitable. However, should a single opponent call, you have to be willing to follow up with another bet on the turn, especially in low-limit online games in which players will routinely take one off on the flop and fold on the turn.

-- Homer

[Thythe]

This clears a lot of stuff up. I typically would bet flush draws instinctively but didn'f fully know all the math behind it.