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icedevil2002
12-07-2004, 04:21 AM
I was wondering if anyone knew the way of calculating the odds of hitting a flush/straight out of a draw by the river i know that a flush has about 9 outs and an open ended straight has 8 outs but then when you are talking about a flush draw you should discount 2 outs when talking about 10 person game. So if you flop a flush draw or an open ended straight draw. whats the are odds that you will hit either one by the river

Mike Haven
12-07-2004, 07:05 AM
when you are talking about a flush draw you should discount 2 outs when talking about 10 person game

why would you do this? is this someone's "rule of thumb" in case you flush but someone makes a full house at the same time?

if that's the reason, i would suggest that it might only be sensible if there are maybe seven or more in after the flop, but at that point you are getting more than sufficent pot odds to try your luck in any case

if you do a "search" or look back through some threads in this forum you will see dozens of posts on how to do these sorts of calculations

icedevil2002
12-07-2004, 01:39 PM
you discount 2 outs in a 8-10 person game because the odds of having any suit in 1-4 so the means odds are two people at the table have the same suit as you.

Dave H.
12-07-2004, 06:04 PM
No offense, but you absolutely DO NOT discount 2 outs as you mentioned. I'm assuming that (for a flush), you are talking about having a four flush on the flop and want to know the probability of making at least a 5 card flush by the river. All you know is that you have 47 unseen cards and that there are 9 of the flush suit somewhere, but you DO NOT assume that they are in someone's hand.

For a good discussion on the flush question, please see my similar question and some great responses at:

Flush odds and Suited Board Odds (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&amp;Number=1296835&amp;page=5&amp;view=c ollapsed&amp;sb=5&amp;o=14)

AngryCola
12-07-2004, 06:07 PM
Dave is right about that. You shouldn't be making that discount. Now, if you had a read on a player that told you he had a flush draw...that would be different.

icedevil2002
12-08-2004, 12:15 AM
See before I said the same thing but the truth is the odds are that someone else at the table has at least 2 of your outs for a flush. Because think about it if you flop 4 to a flush and you think that all nine outs are in there then you just aren't counting everything.Because at a ten person table 1in 4 people will be dealt your suit and if you think about it they are dealt two cards so the odds are even more likely But yet no one has answered my question yet

rybellcamp
12-08-2004, 12:47 AM
Check it out. Having an open ended straight flush draw gives you 9 outs for the flush, and then 6 cards for the straight (as 2 of the 9 flush cards will make your straight flush). So you have 15 outs total (you will make at least a straight 54% of the time with 2 cards to come, and about 32% with one card to come). As for trying to figure out how many outs are in other peoples hand, you can only try to estimate that by using a basic distribution of starting hands table, and calculate approx how often your outs could be dealt out to other hands ( for example, in a short handed 6 way table, and dealing strictly with a flush draw, you will have the following facts: preflop - 2 seen cards, 10 unseen, on the flop - 3 more seen, giving us 37 unseen still to come. Figuring you have 13 cards of your suit, and four accounted for between your hand and the board, you have 9 unaccounted of your suit. With a ratio of 10 unseen in your opponents hand, and 37 unseen still to come, you can estimate approx percentages of where your desired outs may be. Keep in mind though, these percentages will not be significant often enough to necessitate you changing your overall strategy in playing the hand). Hope this helps! Peace

gaming_mouse
12-08-2004, 01:12 AM
[ QUOTE ]
See before I said the same thing but the truth is the odds are that someone else at the table has at least 2 of your outs for a flush. Because think about it if you flop 4 to a flush and you think that all nine outs are in there then you just aren't counting everything.Because at a ten person table 1in 4 people will be dealt your suit and if you think about it they are dealt two cards so the odds are even more likely But yet no one has answered my question yet

[/ QUOTE ]

icedevil,

you are suffering from a common misconception. Please see the following thread for an explanation of where your reasoning is going wrong:

http://forumserver.twoplustwo.com/showflat.php?Cat=&amp;Number=1349286&amp;page=0&amp;view=colla psed&amp;sb=5&amp;o=&amp;fpart=1

gm

gaming_mouse
12-08-2004, 01:17 AM
[ QUOTE ]
As for trying to figure out how many outs are in other peoples hand, you can only try to estimate that by using a basic distribution of starting hands table,

[/ QUOTE ]

Rybell,

This really confuses the issue. You do need to do any such estimates when you are counting your outs. And the omission of such estimates does NOT represent an approximation to the true solution.

When you calculate the chance that the next card is one of your outs, the calculation already accounts for the chance that the card might be in one of your opponent's hand. All you need to know is that the card is "unseen."

gm

rybellcamp
12-08-2004, 01:44 AM
Mousy,
You are right. I seemed to have momentarily suffered from a case of the "two red jack" syndrome. Thanks for the link!
Peace