HOW to calculate EV fast
Posted by Aleksandra ZenFish
Posted by
Aleksandra ZenFish
posted in
Low Stakes
HOW to calculate EV fast
BN: dan1er: $3.90
SB: 19Agnes74: $9.54
BB: shashoualex: $10
UTG: edxv: $16.48
HJ: karocharov: $10.05
CO: lifa_raul: $28.41
SB: 19Agnes74: $9.54
BB: shashoualex: $10
UTG: edxv: $16.48
HJ: karocharov: $10.05
CO: lifa_raul: $28.41
Preflop
($0.15)
(6 Players)
shashoualex was dealt
9
T
9
6
edxv folds, karocharov folds, lifa_raul raises to $0.35, dan1er calls $0.35, 19Agnes74 folds, shashoualex calls $0.25
edxv folds, karocharov folds, lifa_raul raises to $0.35, dan1er calls $0.35, 19Agnes74 folds, shashoualex calls $0.25
Flop
($1.10)
4
8
7
(3 Players)
shashoualex checks,
lifa_raul bets $0.70,
dan1er raises to $3.15,
shashoualex folds,
lifa_raul raises to $5.60,
dan1er calls $0.40, and is all in
Turn
($10.95)
4
8
7
T
(2 Players)
River
($10.95)
4
8
7
T
K
(2 Players)
Final Pot
lifa_raul has
A
7
A
4
dan1er has
5
5
6
6
dan1er
wins $7.83
But that took time
James helped me with fast approx ev alike this
pots need to be right 33% of the time
1/2 need to be right 25% of the time
2x pot need to be right 40% of the time.
But what confused me it was reraised before me so i wasnt sure
i assihned in propokertools 1 villain worst possible hand against mine ( set plus made straight ) and assumed 3rd player will fold or has irrelevant hand ( showed totals 4 percent even when i add him ) so simulation looked like this
http://propokertools.com/simulations/show?b=4d8c7h&g=oh&h1=9h9s6dTd&h2=8s8d5h6s&s=generic
EV calculation after simulation looked like this
0,46x4.95-0.54x3.5
2.227-1.89
+0.337
MY question is
I needed5 minutes for all that , is there some faster way i do it???!!!
Loading 13 Comments...
A txt-file with outs for various wraps (tried to post it here, but the formatting got screwed up):
https://dl.dropbox.com/u/486111/wraps.txt
x = your cards
y = board cards
numbers = outs
numbers in parentheses = nut outs
1) Learn to quickly count outs for your wraps. Just memorize the stuff.
2) Account for Villain's redraws and estimate how many clean outs you have
3) Estimate equity using a simple formula
Here's a quick'n dirty calculation for your wrap vs a dry set (without additional draws):
You have a 2-1 wrap around a connector for 17 outs (11 to the nuts). We'll assume all outs are winning (17) vs a dry set, and then we subtract 1 for the pair we hold, and we get 16. Then account for Villain's redraw to a house/quads. He has 10 outs on the turn, so about 1/4 of the time we hit, he draws out. So we effectively have (3/4)(16) = 12 clean straight outs.
You also have a backdoor flush (~1 out). The flushdraw is not to the nuts, so let's conservatively assume 12 clean outs total (remember, we assumed all straight outs were winners, so it makes sense to disregard the BD flush for some error cancellation).
Then equity. Use the 4x rule for < 10 outs and the 3x + 9 rule for 10+ outs (approximatiive formulas). You get 3x12 + 9 = 45%.
We check that number in ProPokerTools (your hand vs 88** on flop 4d 8c 7h) and get 46%. Pretty much spot on. This seems like a lot of work to do at the table, but you can do this with practice. Learn to count outs accurately, that's über-important., Then subtract outs to account for Villain's redraws and then the equity is just a simple formula.
P.S. You can of course just timebank and plug the ranges into ProPokerTools, but this is the old-school way to do it. Comes in handy if you play live. ;-)
What confuses me more then outs number, i can cope with that in time given for hand is expected value, do i have positive EV to pay something X to get Y or lose X, i somehow fail to grasp that 1 well
If Villain raises pot all-in, you get 2 : 1 and need 1/(1+2) = 33%. If he shoves for 1/2 pot you get 3 : 1, and need 1/(3+1) = 25%, etc.
In your example it was 3.50 to call and a 4.95 pot, so pot-odds = 4.05 : 3.50 and necessary equity 3.50/(4.95 + 3.50) = 41%.
if he is allin i need 33 percnt equity and ye he isnt allin and i need 41 percent equity?
what is 3,5 raise ` POT? and if its apot i need 33 and when i calculate its minumum 41
Very sorry i didnt get it
I get all numbers separately
I get 3.50/(4.95 + 3.50) = 41%. and i get EV calculation after simulation looked like this
0,46x4.95-0.54x3.5
2.227-1.89
+0.337
What i dont get is how these numbers u gave
quote : If Villain raises pot all-in, you get 2 : 1 and need 1/(1+2) = 33%. If he shoves for 1/2 pot you get 3 : 1, and need 1/(3+1) = 25%, etc.
FIt in above or correlate to above calculations
:S ugh
v sorry i still didnt get it , maybe im too tired had loads things to do today slept too lil , ill try tomorrow
3.50/(4.95 + 3.50) = 41%
Now you go to ProPokerTools and see if you have that equity or more. If yes, call. If no, fold. However, don't give Villain just one hand. Give him a range. If you're > 41% against that range, call. If you're < 41%, fold.
If you want to know exactly what the EV is, you can calculate that, but the most interesting part is whether it's +EV (then you call) or -EV (then you fold). That's the fastest way to check if the call is correct or not. Just compare the equity you HAVE (use ProPokerTools) with the equity you NEED (use the pot-odds equation).
P,S, Don't confuse equity with EV. They are not the same thing. ProPokerTools gives you the equity. If you want to compute the EV, you need to put the equity into an EV-equation and do the math, like you did.
It doesn't matter much mathematically whether the board pairs on the turn or the river. When we make our hand on the turn or river, the board will have paired along the way about 1/4 of the time. So we remove 1/4 of our outs and estimate 12 clean outs.
These numbers are estimations. Simple math, but good enough, and easy to do at the table. You'll usually end up within +/- 2-3% away from the true answer.
so 3/4 of our odds should rather be an empiric number that we through in there to help with the math and gets us very close to the truth thanks again.
On the flop we know 9 cards (our hand + flop + 2 of Villain's cards) and there are 43 unknowns. 16 of these are outs, 7 pair the board, and 20 are non-pairing blanks. When we hit an out on the turn there are 42 unknowns left, 10 of them pair the board and 32 don't.
The probability of us ending up with the winning hand is then:
P(hit turn AND non-pairing river) + P(non-pairing blank turn AND hit river)
= (16/43)(32/42) + (20/42)(16/42)
= (512/1806) + (320/1806)
= 832/1806
= 46%
Now we convert this probability to the corresponding number of clean outs, using the approximate 4x rule (3x + 9 for 10+ outs).
46//4 = 11.5
46% corresponds to more than 10 outs, so we use the 3x+9 rule for a better approximation:
3x + 9 = 46
x = (46-9))/3
x = 12.3
Conclusion: About 12 of our 16 outs are effectively clean. So we need to remove 1/4 of them against a set. If you repeat the same calculation for a 4, outer, a 10-outer and a 20-outer and list all the results accurate to one decimal place you get:
4 --> 3.5 (-12.5%)
10 --> 8.0 ( -20%)
16 --> 12.3 (-23%)
20 --> 14.8 ( -26%)
So the 1/4 rule works best for big draws with 10+ outs. But even for a 4-outer the absolute error will only be 0.5 outs (3 vs 3.5). Besides, if we're planning to get it in on the flop with a 4-outer vs a set, we have bigger problems to deal with than small numerical errors.
Note that the only approximation we use in the calculations is the good old 4x (or 3x + 9) rule for converting outs to winning % with two cards to come. This rule is easy to verify (t's not an empirical formula, but a linear approximation of the exact mathematical formula), and similarly you'll see that 3x + 9 is a better approximation for 10+ outs.
I hope this was understandable. ;-)
Be the first to add a comment