FTP Rakeback wrong for hands w/ side pots
This is the question I asked FTP Support:
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Another question regarding rake / rakeback:
6max ring game, 3 players
P1 all-in for 20$
P2 all-in for 40$
P3 all-in for 40$
Mainpot 60$, sidepot 40$
There are 3 reasonable ways this pot could be handled under the weighted-contributed rakeback system:
1. all players pay the same rake (main pot $60, $3 rake, $1 each), the side pot is rake free. Weighted-contributed looks at the RAKE PAID. Each player paid 1$ rake and gets $0.27 rakeback totaling $0.81 rakeback.
2. all players pay the same rake (main pot $60, $3 rake, $1 each), the side pot is rake free. Weighted-contributed looks at the MONEY INVESTED. P1 invested 1/5 of the total pot, P2 and P3 2/5 each. P1 gets 1/5 * $3 * 27% = $0.162, P2 and P3 get 2/5 * $3 * 27% = $0.324 totaling $0.81 rakeback.
3. the rake is split between the pots. Main pot 6/10 * $3 = $1.80 and side pot 4/10 * $3 = $1.20. Here the 2 methods from above produce the same result.
So which one is used?
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And the answer by FTP Support is:
The credit is split by what % of the pot you contributed. In your example, the 2nd method you suggest is the method used for calculating the contributed rake and you figures are correct. Players 1 gets 20% of $3 while players 2 and 3 get 40%.
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result:
HEM uses method #1 which is wrong
It doesn't matter how much rake you contributed only how much money.
The difference is severe:
With M#3 the hand costs for P1 $0.60 - $0.162 = $0.438
With M#2 the hand costs for P1 $1.00 - $0.162 = $0.838 (correct)
With M#1 the hand costs for P1 $1.00 - $0.270 = $0.730 (HEM)
