Odds Question
Can someone give me a hand, I'm having trouble with turning % into odds for and against. If I have four to a flush and there are 9 cards left in the deck to complete my hand I will have roughly 36% chance of hitting (I read that if you have 2 cards to come times your number outs by 4. If you have 1 card to come times your number of outs by 2 to get a rough %). This is where I get confused. The books say I'm a 5-1 dog against completing my flush but if I take 100/36 this equals 2.78 so wouldnt that mean I'm a 3-1 dog ??? What the hell am I doing wrong
Thanks
Wader
Thanks
Wader
Comments
"To change a percentage to odds [against] (to 1), subtract the percentage...from 100 and divide the result by this same percentage.
The probability of hitting a 9 out draw with 47 unseen cards and two cards to come is 35%. Odds (to 1) are
(100-35)/35
=1.86 to 1
A book quoting 5 to 1 odds against making a flush with two cards to come is *way* off. (Even with only one card to come, the odds against making a flush are about 4 to 1, not 5 to 1.)
ScottyZ
Yes. The easiest way is to simply *memorize* the odds of the most commonly occuring draws.
As for the actual calculations, I don't see any nice simplifications, except for rounding off.
For example, you might recognize that (100-35)/35 is pretty close to 66/33 which equals 2. Therefore, the flush draw (with two cards to come) is about 2 to 1 against. (Recall that the actual figure was 1.86 to 1.)
Doing these calculations on the fly if you are not comfortable with mental arithmetic is *not* easy, and there aren't any good tricks that I know of. On the plus side, not being able doing these sorts of calculations in real time at the poker table will not put you at any substantive disadvantage.
ScottyZ
I have a quick scenario for you
Blinds are .50/$1 in an 11 man game, you have K9 clubs, there are 4 callers including you and the sb and bb. So there is a total of $4 in the pot. After the flop there is Ac-8c-6s. One person bets out $4 and everyone folds to you. So the pot is giving you 2-1. Since you need roughly 2-1 you can go ahead and call this bet. The turn is 5d and the original better bets another $4 dollars so the ppot is laying you 3-1 and you need roughly 4-1 to call. By the book you are you not suppose to call this bet?
Except for evaluating all-in situations, thinking in about pot odds in NL is rarely useful. Implied odds are the thing to think about.
In this example, you *cannot* justify calling on the flop simply because the pot odds are 2-1. (This is not to say that calling is wrong here by any means.) This would basically amount to assuming that your opponent is guaranteed to not bet on the turn if a brick comes. Put simply, you *cannot* use the "two cards to come" drawing odds when deciding on flop actions, especially in pot- or no-limit. Calling on the flop lets you see just one card: the turn card. Whether or not you will end up seeing the river, or how much it will cost you to do so is an unknown.
Calling $4 again on the turn may or may not be correct. If your opponent is all-in on the turn after he has bet the $4, then calling is definitely wrong (based on the pot odds). If you and your opponent both have chips left, then there is not enough information in looking at the pot odds alone to determine the correct decision.
In NL (and technically in limit too, but it's especially important in big bet poker), implied odds are the thing to consider rather than pot odds when determining if calls are profitable or not.
ScottyZ
Do you suggest this book to learn more about implied odds?
I'd suggest "Theory of Poker" by David Sklansky.
ScottyZ