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SaintAces
04-15-2004, 10:11 AM
Antes are 10.
1000 chips in play
Home game 6 person tournament.
We are heads up with Person A and Person B.
Assuming players are of exactly equal skill.


what pecent of the time should Person A win with a

**Assuming with a 1:1 chip lead Person A has EXACTLY a 50% chance of winning.

5:1 chip lead
4:1 chip lead
3:1 chip lead
3:2 chip lead
3:4 chip lead
5:4 chip lead

you don't need to find all of these if you don't have the time, but a few would be greatly appreciated!

Thanks in advanced!

Lost Wages
04-15-2004, 10:28 AM
With players of equal skill playing headsup, the probability a player of winning is simply his percentage of the chips. So, with a 5:1 lead player A will win 83.3% (5/6) of the time.

Lost Wages

SaintAces
04-15-2004, 02:00 PM
If it is 6 player - winner take all tourney format - we all start 75 chips.

If I KNOW that I am a better player. Should I be alright with the fact that ALL of the chips but my 75 go to the lesser player. That means 375 to him and 75 to me.

Thats a 5:1 chip lead, making it about 83% he wins --correct? (not including the skill factor)

Is this a situation that you guys will take every time?

ZeeJustin
04-15-2004, 04:19 PM
[ QUOTE ]
Is this a situation that you guys will take every time?

[/ QUOTE ]

Yes, assuming he is worse.

Duke
04-16-2004, 09:46 AM
This depends, actually.

Think of the blinds relative to your stack. With N times the BB in your stack, and 5N times the BB in his stack, you might have enough play. If the blinds were larger than either of your stacks, you'd win exactly as much as your ratios predicted. That's how that number is computed to begin with. All in every hand, and so on.

That's probably a more interesting problem to look at; how much would the blinds affect the outcome? At what point will a guy with a K-1 chip disadvantage be able to win a certain amount of the time when he's a certain amount better than his opponent?

An answer should be in terms of chip count disadvantage, size of blind relative to the stack sizes, and quality of the opponent. The boundary condition should make it fairly clear that the blinds are definitely an important factor. How many times a player wins when playing heads up starting with equal stacks and blinds of size epsilon (who knows the code for that?) would determine that. If he wins x out of y times in that scenario, then he's (x/(y-x)) times as good, and so on.

I'm not sure right now how to factor in the size of the blinds in the final formula, but I'm tired and ill. That's my excuse and I'm sticking to it. So, no equations from me right now, but someone will probably be more awake to quantify some of this stuff while I'm sleeping.

If this problem has been tackled in the past, then please point me to the governing literature so I may either smile and nod or soundly bash it :-).

Good night. Yeah, I keep bizarro hours.

And yeah, general equations = good. Samples and percentages = bad.

~D

SaintAces
04-16-2004, 12:50 PM
anyone have any idea how to do that ?


and
thanks for the great reply Duke

Duke
04-16-2004, 09:22 PM
Well at 0 blinds the player who was behind in chips would have no strategy to win, and the chip leader would just never play a hand and maintain his chip lead. You'd be at a deadlock. The same is true for infinitessimally small blinds, as no matter how much you were blind stealing, the chip leader would be able to just wait for huge hands and maximize his chances of winning.

So at very small and very large blinds, the skillsets don't matter since there is a "braindead" strategy that cannot be surmounted.

So the role of skill will escalate from 0 and approach 1, then drop back down to zero when it turns into all-in every hand because of the blind size.

Now we have a general form for it, but deriving an actual equation takes a bit more work. I can't just guess at 4th order polynomials and end at what feels right after plugging in some constants to later be defined.

Maybe Mason has a clue, or for all I know David wrote about this in his Tournament Hold'em book. I haven't read it. I'll continue to think about it in my spare time, though.

Wouldn't it be something to come up with a poker solution with enough rigor that it could be published in a math journal?

~D

ThinkQuick
04-17-2004, 02:43 AM
If this were a sixTY person tourney where only first place payed, I'd choose to be short stacked, heads up for the win 100% of the time over starting equal with the other 59.
Therefore my answer is the same for the six person.
IS there any reason to consider the numbers as important in this question?

pzhon
04-18-2004, 09:07 PM
[ QUOTE ]
Well at 0 blinds the player who was behind in chips would have no strategy to win, and the chip leader would just never play a hand and maintain his chip lead. You'd be at a deadlock. The same is true for infinitessimally small blinds, as no matter how much you were blind stealing, the chip leader would be able to just wait for huge hands and maximize his chances of winning.

[/ QUOTE ]

This argument is wrong.

There are no infinitesimally small blinds. The stacks may be arbitrarily large in comparison with the blinds, but picking up the blinds is always worth something. If you always pick up the blinds, you will win the freezeout eventually. This does not resemble the degenerate game with no blind.

If you gain a chip with probability 50.1% and lose a chip with probability 49.9%, your probability of winning a freezeout goes to 1 as the size of the stacks increases.

Duke
04-19-2004, 05:27 AM
[ QUOTE ]
There are no infinitesimally small blinds. The stacks may be arbitrarily large in comparison with the blinds, but picking up the blinds is always worth something.

[/ QUOTE ]

I disagree, obviously. Not a lot to say here.

Uh, it spikes really quickly in my opinion, but I'll stand by blinds small enough existing that aren't even worth fighting over.

~D

danderso8
04-19-2004, 07:14 PM
I believe the point at which blinds could be considered "infinitely small" would be where they are small enough that even if the short stack was stealing them every time, enough hands would be dealt that the leader would expect to have several chances with monster hands. In each of those hands, he could expect to get back at least the blind-steal bet from the SS, and eventually, the SS would have a hand he thought was worth playing, even though he knew he was up against a monster. At that point, he would either double up or lose out. So let's say the Leader will only play if he gets AA, and shorty, knowing that, will only come along if he has AA as well. They'll split the pot most of the time, but once in a while one of them will flush. Depending on the chip ratio to begin with, Leader may have several chances to do this, all while maintaining a lead over Shorty until he busts.

Coincidentally, it almost seemed like this was happening (infinitely small blinds i mean) in the home-game tourney I played in this weekend. We were playing with how fast the blinds increased (first tourney too slow, second one seemed too fast...last one, we capped the blinds when they reached what seemed like a reasonably high level. Well, the last 3 guys ended up swapping back and forth for about 2 hours. The fella who had the short stack for the first of those hours ended up winning it.

-dan

pzhon
04-20-2004, 12:09 PM
[ QUOTE ]
I believe the point at which blinds could be considered "infinitely small" would be where they are small enough that even if the short stack was stealing them every time, enough hands would be dealt that the leader would expect to have several chances with monster hands.

[/ QUOTE ]

No.

Even if your subsequent analysis were valid, it would require more than a few hundred times the blinds. You required AA versus AA matchups, which happen 1/270,725 of the time, but further you require that this not split the pot, but a flush happens only about 1/23 of the time, so you need the stacks to be tens of million of times the blinds.

"Infinitesimal" already means something in non-Archimedean ordered fields such as the hyperreals. However, real numbers are Archimedean. That means for every positive real number x, there is some positive integer n so that x is greater than 1/n. If you keep giving up a real blind x, you will give away your whole stack in n steps.

[ QUOTE ]
In each of those hands, he could expect to get back at least the blind-steal bet from the SS, and eventually, the SS would have a hand he thought was worth playing, even though he knew he was up against a monster. At that point, he would either double up or lose out. So let's say the Leader will only play if he gets AA, and shorty, knowing that, will only come along if he has AA as well.

[/ QUOTE ]

If the leader adopts a strategy that bad, then the short stack should throw away AA when the leader bets. If the leader adopts this brain-dead strategy, the short stack will steal the blinds 220/221 of the time, and will give up a minimum raise 1/221 of the time. The result is a random walk that increases 1 chip 220/221 of the time, and decreases perhaps 2 chips 1/221 of the time. If the trailer had 1/6 of the chips at the beginning, then the trailer's chance of winning will be very close to 1, and will be closer to 1 for larger numbers of chips/smaller blinds.

<ul type="square">That is the exact opposite of the blinds becoming negligible. [/list] A crucial statistic to watch is the variance:disadvantage ratio, properly normalized in terms of the total stacks, not chips. The average total variance of a (uniformly bounded) martingale that starts at x and ends at 0 or 1 is fixed, x(1-x). If your variance:disadvantage ratio is high, then you are close to a martingale, so your equity is close to x. If your variance:disadvantage ratio is low, then the drift dominates, and you may win with probability very far from x.

Suppose you construct simple strategies that have arbitrarily large variance:disadvantage ratios against all opposing strategies as the number of chips each side has increases. Then, as the blinds decrease, either player could fall back on a high-variance strategy to win with probability close to the fraction of the chips. That would be an argument for saying that the skill would be negligible as the blinds shrink. However, I don't believe such a family of strategies exists. If you disagree, the burden is on you to construct such a strategy.

Your suggested strategy has a variance:disadvantage ratio against the above counterstrategy that decreases to 0 as the blinds shrink. The counterstrategy wins with probability approaching 1 as the blinds decrease even if the counterstrategy starts with 1/1000 of the chips.

Duke
04-21-2004, 08:51 PM
[ QUOTE ]
However, I don't believe such a family of strategies exists. If you disagree, the burden is on you to construct such a strategy.

[/ QUOTE ]

OK. You're right. The idiot strategy does not work for tiny blinds.

~D