EV, Dont understand.

[iNsChris]

One part of poker i dont understand is EV.

I know pot odds, Implied odds, Odds to improve(outs etc).
What is EV? Its % of some kind to do with profit? or chances of winning with the cards you hold?

A explanation is appreciated, Thanks.

[Chex]

Simply a decision that will make more money...+EV
...decision that will lose money..-EV

[iNsChris]

yeh understand that, But whats the logic behind it?

How do i calculate EV? Hows it work?

Thanks.

[Jeffage]

Basically in poker, you want to maximize the expected value for every play you make. What particular play in a certain instance will yield the most LONGTERM profit? A bet which is profitable in the long run is +EV, one that isn't is -EV. Often it's a battle between which play maximizes EV. Ex. You have AA UTG. You raise, 5 people coldcall, comes back to the BB and he 3-bets. You cap and everyone calls. If the flop comes with a flush draw and the BB bets, what's your play? Well, in this case...waiting till the turn would have a higher expected value than raising instantly. This is b/c many draws will get an incorrect price to call 2 cold on the turn where calling 2 cold on the flop in this large pot would be correct. It's really just a way of thinking about the game moreso than something like odds (which you calculate). The more +EV plays you make, the better you'll do. Also some slight plus expectation plays come with high variance. So if on a short roll in a big game you may want to sacrifice some EV to avoid variance. ETC.

Jeff

[iNsChris]

Ah i see, So its more of an Overview, Incomparison to potodds/Odds to improve which are more of a "tool" used whilst you play?

So reviewing a chart now and again might be wise if you need to tighten some starting hands etc?

[SheridanCat]

[ QUOTE ]
Ah i see, So its more of an Overview, Incomparison to potodds/Odds to improve which are more of a "tool" used whilst you play?


[/ QUOTE ]

Each decision you make at a poker table has an expected value, either + or -. So, when you're using pot odds, implied odds, etc. to guide your play, each option has an expected value. Over the long run, the +EV plays will show a profit (assuming you aren't making -EV mistakes that negate your positive plays).

This is why we want to play tighter than our opposition. If we are starting out with better hands than our opponents, we are in a better position to make +EV plays later on. Of course, that's not the only place we gain expectation, but it's a good place to start.

[ QUOTE ]

So reviewing a chart now and again might be wise if you need to tighten some starting hands etc?

[/ QUOTE ]

I'm not sure I understand your point. It is important to not only know the charts but why those charts tell you what they tell you. Understanding the theory behind the charts is the key to winning in the long run.

Regards,

T

[Pov]

[ QUOTE ]
yeh understand that, But whats the logic behind it?

How do i calculate EV? Hows it work?

Thanks.

[/ QUOTE ]

EV is calculated by summing the product of the probability of potential outcomes and their expected profits. So to re-use the classic dice rolling example:

You make a bet with Suzie. You'll roll a die and on a result of 1-5 you'll pay her $2 and on a result of 6 she'll pay you $12. What is your EV?

Roll of 1
probability: 1/6 ~= 16.67%
profit: -2.00

Roll of 2
probability: 1/6 ~= 16.67%
profit: -2.00

Roll of 3
probability: 1/6 ~= 16.67%
profit: -2.00

Roll of 4
probability: 1/6 ~= 16.67%
profit: -2.00

Roll of 5
probability: 1/6 ~= 16.67%
profit: -2.00

Roll of 6
probability: 1/6 ~= 16.67%
profit: +12.00

(-2*.1667) + (-2*.1667) + (-2*.1667) + (-2*.1667) + (-2*.1667) + (12*.1667) ~= .33

So your EV for EACH roll of the die is 33 cents. Even though you will lose $2 most of the time, you theoretically earn 33 cents regardless of the outcome of that specific roll. After many rolls your profit will average out to match your EV.

[iNsChris]

AH i see, K thanks guys - So EV will prob give lots of varience (I.e. the dice example) but you win in the long run(Acorrding to numbers anyhow).

[Pov]

[ QUOTE ]
AH i see, K thanks guys - So EV will prob give lots of varience (I.e. the dice example) but you win in the long run(Acorrding to numbers anyhow).

[/ QUOTE ]

The EV is independent of the variance. For instance we could make a different bet: We roll the die and on a value of 1-6 you get $1. Your EV is $1 and your variance is zero.

[AKQJ10]

This is all true (about EV and variance being independent), but not something one needs to worry about to get the concept of EV.

Chris, you're correct, the first die example would have substantial variance. But the point is, a +EV proposition makes you money in the long run, even though in the short run you might just get unlucky.