Quote:
Originally Posted by johnnyBuz
I don't understand all of the theoretical workings of EV, but how can it take into account future bets?
This is a fairly simple question to answer, I think. I sort of laid this out in my RIO thread, but let me try to take a crack at it again now.
Your flop call was $55. After you make this call, the turn pot is $195, which, for the purposes of future bets, I will call dead money.
Now there are finitely many turns that can come up. For each possible turn, your EV
from the turn onward is going to be some amount, probably some but not all of which are the same. For example, if you catch a card that has your opponent drawing dead, your EV is going to be the pot plus whatever you can extract. If you try to bluff and get called, your EV is negative whatever you bet (adjusted for the possibility of a river suckout or successful river bluff). And so on. For example, you know on a low black card that you will fold to a bet, and given the range you assigned, you know one is coming; so the EV that comes from those turns using this model is 0.
So you'd take all of those finitely many terms, multiply each by the probability of the turn coming that leads to that EV, and add/subtract it all.
Since you called 55 on the flop, you need that total to be more than 55 for a flop call to be +EV.
When people (including me) are saying that you should fold the flop, essentially what they/I have said is that you're overestimating your EV on various turn cards in a way that makes it extremely hard to recover the $55 you called off.
For example, take your backdoor flush draw. After you turn it, your EV is a separate calculation from when you called the flop. And it's probably positive. However, once you compute what it is, you have to multiply that EV by the probability of you turning that draw to see how it contributes to your flop EV.
The "tricky" cards that I and others were harping on, though, were not diamonds, but instead hearts, jacks, and tens. For example, on a jack, you will only sometimes win the pot, and when you do, it's not clear how much you can extract. But other times you lose the pot and you lose more money. All of those possibilities sum in a weighted average to see how much a J turn contributes to your flop EV. It might be positive, but even if it is it's not as big as you probably want to think it is. And because you have so few outs for your hand to improve, a drag on your EV on a J turn is a HUGE profitability killer.
The same goes for trying to bluff a heart turn. If it works, you win the pot. But if it doesn't work, you lose money. So you need to figure out how much you can win from Villain folding right away (195 times his fold %), how much you can win if you get him to fold to a river barrel, and then also how much you lose if you bluff and it doesn't work. They sum in a weighted average, and so, even if that sum is positive, it's probably not enough to help you get to the $55 you need, especially when you multiply by the probability that a heart falls on the turn in the first place.
If you play around with some numbers I think you will start to see why people are saying it's hard to get a reasonable-looking sum that gives you back the amount of your flop call, with the flop range you assigned.