I have been to the HM site which states
'
Expected Value or EV is a mathematical formula based on when a hand goes all-in before the river. This report can be viewed in table or graph format.'
- All-in EV is only calculated based on hands which were all in before the river since equity on the river will always be 0% or 100%. Hence, the river is irrelevant.
This is their notes.
EV $ Diff (found in the Hands Tab)This is calculated by taking your
equity% of the total pot when you go all in and comparing that to what you actually won. So let's say I go all in with AA on an Axx flush draw flop against a flush draw. I'm 80.5% to win with my set in a $400 pot.
80.5% x $400 = $322 so what it's saying is on average that I should win approximately $322 on average when I go all in with a set of Aces here vs. his flush draw.
If I win, I would win $400, so I've won $78 more than I would on average i.e running good/okay. If I lose, I win $0, so I'm running $322 worse off than I would on average so im running bad.
EV $ Diff is displayed as minus when you win more than you should and a + sign when you lose more than you would with average luck. So in the examples above, when I lost with AA as a big favorite, my EV $ Diff would be displayed as +$322.
This is calculated by taking the actual amount won and either deducting or adding the amount you would have won with average luck.
http://hm2faq.holdemmanager.com/questions/1212/What+is+EV?+(Expected+Value)