Odds on turn and river

[Fahrenheit451]

Example:
I have 2 spades and after flop there are 2 spades on board.
My odds of getting my flush on turn are 4:1, but on river 2:1.
Which one to take into account ?
If pot odds on turn is 3:1 should I call ?
If I call and not get my flush on turn, villain can offer me worse pot odds, say 2:1 and it will not be profitable to call.

 

[AlexTheOwl]

Using the "rule of two and four", you have about an 18% chance of getting a spade on the turn (9 outs * 2).

If you don't get a spade on the turn, you will have about an 18% chance of getting one on the river.

Let's say you go all in on the flop. Now you are guaranteed to see both the turn and river if called, so your chance of a spade is about 36% (9 outs *4).

So if you are all in on the flop - or so close to all in that you would never fold to a turn bet - use the higher number.

Otherwise, it's a bit tricky.

If you are likely to be asked to call a big turn bet that would require you to fold, use 18%.

If you think there is about a 50% of a big turn bet, then a good estimate would be to "split the difference" ((36 - 18)/2)+18 = about a 27% chance of seeing a spade before the hand ends.

 

[wrabinho]

you maybe had odds but if there no lucky you got nothing.

 

[Fahrenheit451]

AlexTheOwl - Thanks, much clearer now !

 

[Fahrenheit451]

you maybe had odds but if there no lucky you got nothing.

If you are talking about one hand, you are probably right.
In the case of 1000000 hands you will get what odds predict.

 

[Vilgeoforc]

You need to count the odds for each street separately. That is 4:1 on the turn and 4:1 on the river.
But if the opponent went all-in on the flop you have to count the odds on two streets at once. That is 2:1.
In the first case the call 3:1 unfavorable. The second is acceptable.

 

[Lorpugo]

also if you have ace of spade and put your oppo on one pair you have 3 more outs the aces