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Judd
03-28-2010, 01:14 AM
I found a bug today with the all in equity calculation. In a multiway pot, when you are all in preflop, but the other players are not, your equity is calculated at the point at which the other players are all in, not when you are all in.

Judd
03-28-2010, 01:16 AM
Here is a hand example, my equity for this hand is calculated at 5.1% when it should be 77%:

PokerStars Game #12345678910: Hold'em No Limit ($0.50/$1.00 USD) - 2010/03/27 21:52:20 PT [2010/03/28 0:52:20 ET]
Table 'Luscinia' 6-max Seat #3 is the button
Seat 1: MP ($135.05 in chips)
Seat 2: CO ($106.85 in chips)
Seat 3: BTN ($71.60 in chips)
Seat 4: SB ($103.70 in chips)
Seat 5: Hero ($100 in chips)
Seat 6: UTG ($113.65 in chips)
SB: posts small blind $0.50
Hero: posts big blind $1
*** HOLE CARDS ***
Dealt to Hero [Kh Kd]
UTG: raises $2 to $3
MP: calls $3
CO: folds
BTN: folds
SB: calls $2.50
Hero: raises $11 to $14
UTG: raises $18 to $32
MP: folds
SB: calls $29
Hero: raises $68 to $100 and is all-in
UTG: calls $68
SB: calls $68
*** FLOP *** [2s Ah Jd]
SB: bets $3.70 and is all-in
UTG: calls $3.70
*** TURN *** [2s Ah Jd] [Qs]
*** RIVER *** [2s Ah Jd Qs] [8s]
*** SHOW DOWN ***
SB: shows [Kc Qd] (a pair of Queens)
UTG: shows [Jc Jh] (three of a kind, Jacks)
UTG collected $7.40 from side pot
Hero: mucks hand
UTG collected $300 from main pot
*** SUMMARY ***
Total pot $310.40 Main pot $300. Side pot $7.40. | Rake $3
Board [2s Ah Jd Qs 8s]
Seat 1: MP folded before Flop
Seat 2: CO folded before Flop (didn't bet)
Seat 3: BTN (button) folded before Flop (didn't bet)
Seat 4: SB (small blind) showed [Kc Qd] and lost with a pair of Queens
Seat 5: Hero (big blind) mucked [Kh Kd]
Seat 6: UTG showed [Jc Jh] and won ($307.40) with three of a kind, Jacks

netsrak
03-28-2010, 07:12 AM
The multiway calculation is not a bug, its the way it works.

See this: FAQ - Hold'em Manager Poker Tracking Software :: EV Explained (http://faq.holdemmanager.com/questions/120/EV+Explained)

Judd
03-28-2010, 11:43 AM
That doesn't seem right, shouldn't my all in EV be calculated at the point that I was all in? I can understand that the EV can't be calculated if one of the players ends up folding, but when we know all the cards it should be calculated at the point I'm all in, which in this case was preflop, not on the flop.

morny
03-28-2010, 12:29 PM
Its a valid point and the arguments for an against are discussed in detail in that video/FAQ. You could also argue that its unfair that the other 2 guys EV was calculated preflop when they didn't get all in preflop but on the flop

Judd
03-28-2010, 12:49 PM
Wouldn't it be correct to have multiple EV calculations then? One when they were effectively allin preflop against me, and one where they were all in against each other for the remainder of their stacks? Maybe this is too complicated of a situation to calculate correctly? If that's the case then I can just ignore the EV.

I didn't notice the video in the FAQ, will watch it when I have some more free time.

Patvs
03-28-2010, 05:44 PM
If we DO show your $EV when you're allin preflop and your two opponents have a (allin) showdown on a later street (so when we know all the cards)...

And we DON'T show your $EV, when one of the two opponents FOLDS on a later street, it messes up the long term EV results.


------------

Why "EV by street" is a bad thing:
Best explanation here: http://forums.holdemmanager.com/3rd-party-programs-compatible-holdem-manager/16665-enter-sect-7.html

Summary of that thread:
Example:
- you have AA, you raise to 80% of your stack, donkey calls, flop comes K83 rainbow.
- you then go all-in, no matter the flop, because you're committed.
- out of 100 times, 88 times donkey folds.
- 12 times donkeys calls with a set (33/88/KK).
What YOU want:
It shall do no computations for the 88 times where donkey folded--> "no more calculation". (when we DON'T know all the cards)
But for the 12 times when donkey calls with a set "Show that I had invested most of my stack with the best hand preflop, and that you got unlucky". (when we DO know all the cards)

So although you ran good by having donkey folding 88 times out of 100. EV by street focuses on the 12 times where donkey hit his set and tells that you're running below EV.
This is a well-known gambler fallacy. And this is why "EV by street" should not be implemented.

Judd
03-28-2010, 06:30 PM
I'm not looking for street by street EV, I'm looking for EV at the point you were 100% all in, not 80% all in, and also at the point the other 2 players were all in. 2 seperate EV sitiations, but not street by street. I hope that makes sense. Are you saying they are essentially the same thing?

edit: I guess it is for the other two players, so that makes sense now.



If we DO show your $EV when you're allin preflop and your two opponents have a (allin) showdown on a later street (so when we know all the cards)...

And we DON'T show your $EV, when one of the two opponents FOLDS on a later street, it messes up the long term EV results.


Am I correct in assuming that no matter how the EV is calculated in the hand I posted, that the EV will not be entirely correct? Is the way it's down now more correct than if it's done another way?


Thanks for the replies, hope I'm not being too much of a pain.

Patvs
03-28-2010, 09:29 PM
Your situation is similar to the EV by street example, in the sense you screw up the EV if we DO assign you EV when we DO know your opponents holecards,... and DON'T assign EV when we don't.
Assigning 0 for BOTH situations is more fair. Equally fair would be to ALWAYS assign EV (but then we ALWAYS need to know the opponents holecards)
The end result in the longterm for both methods will be the same outcome.


The "problem" with EV:
A: If a player has 0 outs, or
B: the allin situation takes place on the river there is NO EV DIFFERENCE.
C: If a shortstack goes allin preflop, and is called by two bigstacks. And the two bigstacks continue to bet on the flop, turn or river, this situation is treated as situation B. (EV = 0)
Fozzy: "You can't calculate all-in equity if you don't ALWAYS know the hands you are up against."
D: If you commit 80% of your stack with the best hand, but your last 20% goes allin with the worst hand, the $EV Difference will be calculated by your entire stack.


Note: Tristanblue writes "it's precisely because EV by street does nothing to your adjusted-graph on these cases where the opponent folded that it is incorrect."

But what if your opponent never folds? Suppose there are two players A and B. Player A has AA, B has KK. (both have $100 stacks). They commit half their stack preflop and the flop comes AK6. Player B (KK has 1 "out") to win the hand.
If I would play this hand I would always make sure I'm allin on the turn.
However Player X always commits the rest of his stack on the flop and turn *except for one dollar*. And he commits on the river.
Of course, 4% of the time, the rivercard is the case King. Player X's EV Diff is always 0.
My EV Diff is -$4 (96 out of 100 times) and +$96 (4 out of 100 times)
So our EV graph actually looks the same after 100 of these hands.