Thinking about bubble play

[ZeroPointMachine]

Here’s a situation I’ve been examining lately:

-On the bubble with even stacks
-Hero is BTN or CO
-Hero holds a marginal pushing hand assuming calling ranges are accurate.

The assumption is that if the calling ranges are accurate that the push is automatic.

However, one of the fundamental assumptions of ICM is that if Hero folds the hand will be folded around.

SNG PT does not calculate your increase in equity if someone gets taken out without your involvement. You can simulate it by setting up the hypothetical next hand and looking at your fold EV. Obviously the jump in EV is very large (you are ITM now). The tricky part is quantifying how often you can expect this result.

Some of the factors to consider:

-The level of blind play is very important. There are scenarios where the blinds can be expected to battle (correctly) 25% of the time or more.

-Discounting for the upcoming blinds is very important. However, I’m not sure how to correctly discount the button.

I’ve just started on this last night and I don’t have any of the numbers with me at work. Some of the results were pretty interesting though. I plan to do some more work when I get home adjusting the stack sizes, blinds and ranges to try to identify when this might apply.

Has anybody looked at this before?
Are there other factors I need to be considering?

[ZeroPointMachine]

Okay, I’m a little disappointed that nobody responded to this post. [img]/images/graemlins/frown.gif[/img]

Let me try it with some numbers.

Bubble Hand:
Party 20+2, even stacks of 1600, 150/300 blinds, equity modeling set at 50/50, Calling range set at Maniac
Hero is CO with 6 [img]/images/graemlins/heart.gif[/img]6 [img]/images/graemlins/diamond.gif[/img]

EV Fold 24.1%/$48.11
EV Push 24.8%/$49.59

Push = +0.7%

Pretty cut and dried. Right?
But what happens if the hand isn’t folded around? We’ve already stated that SB and BB are calling 23.3% of hands against a push. How many hands will BTN or SB push? Does it matter?

Let’s assume you fold and BTN or SB push and get called and it’s not a split pot. Now were ITM.

ITM hand:
Let’s say that BB called SB push and won. Who wins or loses has very little effect.
Blinds are still 150/300, equity modeling still set at 50/50

BB/Hero 1600
SB 1600
BTN 3200

Hero’s EV is now 29.4%/$58.77 if BTN pushes and 29.0%/$57.97 if SB pushes and 30.4%/$60.83 if you get a walk in the BB. If the three outcomes are equally likely that’s an average of 29.6% EV.

Average gain compared to previous hands Fold EV is 5.5%EV.

How often do you need “action” on the hand for this to be greater EV on average than pushing the previous hand?

.7 / 5.5 = 12.7%

If there will be “action” on this hand 13% of the time or more folding is now superior to pushing.
How often will you get “action”? I don’t know. That involves putting each villain on a pushing range as well as a calling range. However, it wouldn’t be a terrible starting point to look at them being the same.

BTN pushes 23% of the time and gets called by SB 23% of the time and by BB 17.9% of the time.

.23 * (.23 + .179) = 9.4%

SB pushes 23% of the time gets called by BB 23% of the time.

.23 * .23 = 5.3%

That means you get “action” 14.7%.

So, you get the 5.5%EV gain of making the money 14.7% of the time you fold.

.147 * 5.5% = +0.8% EV

I see situations all the time where the SB has shown that he knows what to do when it is folded to him and the BB is a typical 22 donk. How often can you count on action in a situation like that?

Any and all thoughts welcome.
If I’m completely wrong and confused here please set me straight.
My e-penis is kinda small and pathetic but completely flame proof. [img]/images/graemlins/tongue.gif[/img]

[tigerite]

This is why I like an edge of at least 0.5% on the bubble, I believe this not only allows for my presumption to be better than those left, but also for situations like this happening. It's pretty impossible to estimate, though. I think SNGPT's "equity calculation" stuff attempts to add it into the equation but it's far from perfect.

I'll also fold if the ranges are close for the same reason, like say they all have to call 12% or more, if I think this is likely but a battle might happen further up the field then I might look for 17% to do the push.. this is where the "feel" comes into ICM, it's not completely all mathematics.

[ZeroPointMachine]

What I've seen so far makes me think the minimum margin for a push in this situation should be more like 1.0% than .5%.

[pooh74]

If I am understanding you correctly, Don't you think these factors are either:

1. too small to have an appreciable effect on overall EV or:

2. So highly table/read dependent that you/we kind of feel these things out when confronted with the situation. (i.e. noticing a grudge match over a couple of orbits is a very good read...maybe .7 is not enough as it normally would be-IOW "not worth it")

I mean to say, we all sort of do this semi-consciously already. Making a science of it, or using bottom-up reasoning, is just not the way I see it. But I think there is definitely a valid point in your post.

[ZeroPointMachine]

[ QUOTE ]
If I am understanding you correctly, Don't you think these factors are either:

1. too small to have an appreciable effect on overall EV or:

2. So highly table/read dependent that you/we kind of feel these things out when confronted with the situation. (i.e. noticing a grudge match over a couple of orbits is a very good read...maybe .7 is not enough as it normally would be-IOW "not worth it")

I mean to say, we all sort of do this semi-consciously already. Making a science of it, or using bottom-up reasoning, is just not the way I see it. But I think there is definitely a valid point in your post.

[/ QUOTE ]

Trying to find out if they are too small is part of what I'm looking at.

I've made a few posts here arguing that there are times when you should pass on +EV pushes. They are usually greeted with "EV is EV is EV and you are a moron" or "you can't argue with the math".

I was trying to demonstrate here that the math of ICM does not completely solve the problem.

I have heard a bunch of explanations for the .5% margin for a push. I have never seen it stated that it is meant to account for the possibility that the hand will not be folded around if you fold. I would venture to guess that many ICM bushbots don't even realize that a fundamental assumption of ICM is that if you fold the hand will be folded around.

[tigerite]

I certainly do realise it, but it's very hard to gauge how much to fudge the figures so to speak to allow for it. Especially as, if you push then they both may call anyway, given that they might have tangled in the first place, and then you're in a 3-way all-in which you can't calculate except for with PokerStove etc.

I think the only way is to try to give people slightly more of a calling range rather than change the minimum EV you're looking for, it's too difficult.

[pooh74]

[ QUOTE ]
I certainly do realise it, but it's very hard to gauge how much to fudge the figures so to speak to allow for it. Especially as, if you push then they both may call anyway, given that they might have tangled in the first place, and then you're in a 3-way all-in which you can't calculate except for with PokerStove etc.

I think the only way is to try to give people slightly more of a calling range rather than change the minimum EV you're looking for, it's too difficult.

[/ QUOTE ]

Thats exactly what I think is best...I over compensate with calling range. If "maniac" seems a little too loose a calling range, (i.e. He'd never call with 22) I keep it there anyway and then see where I am at. I think its important to basically not miss the clear +EV bubble situations.