Exploiting your opponents errors.

[RogueRivered]

No it isn't. Folding has an - EV its just usually significantly worse than calling

Everything I have read leads me to believe that you shouldn't look at the money already invested -- it's not yours any more -- it's gone. Each decision is separate after that point. The new situation would have never come up without the original investment.

 

[Stu_Ungar]

Everything I have read leads me to believe that you shouldn't look at the money already invested -- it's not yours any more -- it's gone. Each decision is separate after that point. The new situation would have never come up without the original investment.

Most of the time I would agree with this. But I think that its explained this way to prevent people from calling simply because they have already invested money. So most of the time its correct to ignore the money already in the pot.

However an ev of 0 is a break even play. It simply means that the outcome will neither cost nor make any money.

So if every fold has an EV of 0, then folding the absolute nuts should be seen as a break even play.

 

[widowmaker89]

No, folding is zero EV. If you fold you dont make or lose money. If you have the nuts and fold its zero EV. Its a terrible play since if you bet or call you have a positive EV but that doesnt make it negative.

 

[Stu_Ungar]

Well I decided to do a bit of research on the topic and so typed "EV of Folding" into google.

The First hit was a CC post from a year ago!!!

https://www.cardschat.com/forum/gen...ng-ev-folding-questions-about-calling-105053/

It does seem that myself and C9 have gone through a very similar thought process at some point in time!

 

[RogueRivered]

A half pot raise from me is 4BB giving him an 11.5 : 4 decision (about 2.9 : 1) he needs pot odds of 4:1 to call (actually 4.22 : 1) so he has made a mistake.. I am happy he is a donkey etc etc.
But how big is his mistake?
Well to justify calling 4BB, the pot needed to be about 16 BB ( this would give him his 4 : 1 odds needed )
The pot was 11.5BB and he needed 16BB to justify the call so his mistake was 4.5BB (16 – 11.5).
So calling is a mistake, it has a negative equity but its not that big of a mistake, its 4.5BB

Part of your argument here is based on your assumption that your opponent needs 4:1 odds to call. This is incorrect. You are assuming he has two diamonds, and let's say you are right. Which two diamonds is he playing? Either high ones or connected ones, I would think. If you put these cards into PokerStove, you find that you might actually be an underdog at this point (if he holds KdQd, you are an underdog -- two overcards could beat you in addition to the flush.) About the best you could hope for is for him to have Ad low-d, which you would have dominated with your J should an ace appear on the board. Even something like 8d7d is only a 1.5:1 underdog. Therefore, you are the one making a mistake in most scenarios. Why not check now and see what comes on the turn? Then you can make a better decision at that point.

I also don't think you can say your opponent has made a mistake if he calls your pre-flop raise and then decides to give up on the hand. He has no way of knowing what will come on the flop. It is not -EV for him to fold a past decision -- only current and some future (implied odd) decisions are relevant. You could just as easily make a bad call pre-flop and a good one post-flop as the other way around.

P.S. What are you going to do if he puts you all-in with a re-raise after your flop bet?

 

[Stu_Ungar]

Part of your argument here is based on your assumption that your opponent needs 4:1 odds to call. This is incorrect.

TBH that makes no difference on a logical level. I made the assumption to simplify the numbers. If you need to be sure of this then just go back and change all of the raises such that the pot odds given are 4.22:1, Then use drawing odds of 4.22:1 .. the net error will be a little different but not so much that the asumption changes what is being shown.

I did acknowledge this in the first line.

A half pot raise from me is 4BB giving him an 11.5 : 4 decision (about 2.9 : 1) he needs pot odds of 4:1 to call (actually 4.22 : 1) so he has made a mistake..

Its just an example. It doesn't really matter so long as you stick to a convention.. rather than use drawing odds of 4.22:1 requiring me to adjust the pot odds to 4.22:1 I used some approximations on the odds required to draw (4:1) but as I was consistent throughout with this it all evens out in the end.

There are also further aproximations used on the pot sizes.. thats partly why I didnt express the final answer in terms of a ratio.. there are far too many aproximations to be 100% precise, however the mistake made by the opponent in calling the 3/4 pot raise is significantly bigger than the 1/2 pot raise. Had the valuse been similar then there would have been a need to go back and use exact numbers, but as the difference was clearly noticable ther is no real need.

 

[RogueRivered]

I don't mean that 4:1 isn't 4.22:1. I mean the odds to call are way better than that, mostly better than 2:1, and in some cases you are the underdog, so it doesn't matter how much you bet -- your opponent can never make a mistake by calling (if he knew you had TPTK). (Remember the Fundamental Theorem of Poker that you quoted recently.)

 

[Stu_Ungar]

I don't mean that 4:1 isn't 4.22:1. I mean the odds to call are way better than that, mostly better than 2:1, and in some cases you are the underdog, so it doesn't matter how much you bet -- your opponent can never make a mistake by calling (if he knew you had TPTK). (Remember the Fundamental Theorem of Poker that you quoted recently.)

Im not sure what you mean. The odds are about 2:1 if you can get all in or if you can guarantee that the turn will be checked, otherwise its 4:1 on each street.

Is that what you are saying?

Edit: do you mean when he has more outs say when he has a flush draw but also holds a pair. I would have thought that in that case even though he has outs to two pair, I also havethe same number of outs to two pair so they cancel out

 

[Stu_Ungar]

Actualy I do see what you are saying now. I put a scenario into pokestove and im a 2:1 favourite. Why am I only 2:1? I have a board where he he holds no pair and no 1 card draw!

 

[RogueRivered]

Im not sure what you mean. The odds are about 2:1 if you can get all in or if you can guarantee that the turn will be checked, otherwise its 4:1 on each street.

Is that what you are saying?

Edit: do you mean when he has more outs say when he has a flush draw but also holds a pair. I would have thought that in that case even though he has outs to two pair, I also havethe same number of outs to two pair so they cancel out

Well, yes, I am assuming that there are two cards to come after the flop. Isn't that the way to calculate odds? PokerStove does it this way. When I put in the AhJc and say 8d7d with a Jd6d3c board, it gives the equities as 60% for you and 40% for your opponent. That's 1.5:1, right? Now if a diamond doesn't fall on the turn, we reevaluate and the 4:1 is more correct. If I enter the same info except use KdQd for the opponent's hand, he is actually a favorite, so it would be a mistake for him to fold no matter what at this point. Maybe next street he could make a correct fold, but you'd have to bet a lot to ruin his odds. He's still only a 2:1 dog with one card to come.

 

[Stu_Ungar]

You only use the 2:1 odds for two cards to come if you see both for the same price. If you pay on the flop to see the turn and again on the turn to see the river then each street is compared to 4:1.

If you pay on the flop and check the turn then both cards were paid for on the flop so then the odds are 2:1.

This must be how PS is calculating it.

But you dont use 2:1 just because 2 cards are left to come.. you have to be able to buy both cards in one payment to get 2:1

 

[RogueRivered]

You only use the 2:1 odds for two cards to come if you see both for the same price. If you pay on the flop to see the turn and again on the turn to see the river then each street is compared to 4:1.

If you pay on the flop and check the turn then both cards were paid for on the flop so then the odds are 2:1.

This must be how PS is calculating it.

But you dont use 2:1 just because 2 cards are left to come.. you have to be able to buy both cards in one payment to get 2:1

So I'd be correct to go all-in as a semi-bluff. That would make it difficult for you to respond with just TPTK.

I think in calculating odds on the flop for a flush draw, it is 4:1 twice, or about 2:1. Of course, there could be other ways to win besides the flush, so the odds are even better. It's impossible to know what will happen on the later streets, so you go with what you know at the point of decision, and that is that you are about 2:1 to make your flush.

 

[Stu_Ungar]

So I'd be correct to go all-in as a semi-bluff. That would make it difficult for you to respond with just TPTK.

Yeah completely.. You would generate tonns of fold equity and even if I called you would have correct odds (assuming your all in was pot sized..or there abouts) because you are now seeing 2 cards with one 'payment' so you need only 2:1. If you shove and he calls.. its the same as him shoving and you calling.. provided you are getting about 2:1

 

[zachvac]

I'm confused, a few things though:

- folding is always 0 ev. Argue with it all you want but it's the convention much like freezing point of water is 0 degrees C. For any decision, a fold is by definition 0 ev.

- I thought the initial part of this was purely theoretical. If we want to be even more realistic we have to look at the fact that if villain turns his flush, he will likely get at least one bet out of you holding TPTK. So although it is true he's not 2:1 to hit on one street, he has implied odds such that it still is correct for him to draw knowing you have TP as long as you don't know for sure he has a flush draw

- Biggest thing I think we should get back to discussing the OP, which was a good start. I think you made a few logical errors. But when we go back and forth and all the details that happen in a real hand it just gets too hard to focus on the central point. I don't think Stu is even arguing against a call being correct in that spot, but the main reason it is correct is because you make a small theoretical mistake and when you hit the opponent makes an even bigger theoretical mistake by calling a bet or betting for you with TPTK and 0% equity.

 

[zachvac]

Yeah completely.. You would generate tonns of fold equity and even if I called you would have correct odds (assuming your all in was pot sized..or there abouts) because you are now seeing 2 cards with one 'payment' so you need only 2:1. If you shove and he calls.. its the same as him shoving and you calling.. provided you are getting about 2:1

ok this is an important point too. If we ignore fold equity it is not a good shove, and we do not get odds. If we ignore fold equity it is assuming that villain just shoved into us with TPTK and we are considering calling. Basically the question we ask is are we already pot committed? If we are it's a call/shove. But it's pretty clear that in most cases simply calling a preflop raise does not commit you to stack with a flush draw.

Luckily there is such a thing as fold equity, and a lot of people will be (correctly) folding TPTK.