negative EV in sngs

[evertonroar]

Hi,

HEM seems to be calculating $EV from my sngs incorrectly. This is for Full Tilt and I have updated to the latest version with no changes.

The main reason i can see there is a problem, is that I often end up with -$EV for the entire tournament. My understanding is that this would mean that I actually lost more than my original buy in which is off course not possible.

any hintys you can give me to fix this (or alink to a thread where this has been dealt with before)?

thanks

[netsrak]

Please zip and mail the original handhistory files (you find them in the HM archive folder or in the handhistory folder of your poker client) together with a link to this thread and an explanation of the problem to support@holdemmanager.net. We will then try to reproduce the problem.

[Patvs]

Don't sent us your hands. There is no SNG EV bug. What you're experiencing is by design.


When we worked on EV implementation we made a decision that allow for "impossible" EV values - this was after consulting with many stat experts. Forcing EV to be no lower than $0 and no higher than the win amount would cause a bias issue over larger samples so we did not include any caps.

To imagine a case where you would have a negative EV imagine a tourney where you won an all-in initially where you were an underdog. You are now "lucky" as far as the overall tourney. On the next hand you call an all-in bet on the river and lose. You won $0 in the tourney and you were still lucky so you have a negative EV.

I know it might not make a lot of sense when you look at an individual tourney but over larger samples (which is the main purpose of the EV line) capping the values would make the results incorrect.