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philopker

06-30-2005, 03:31 AM

If you have two connectors in your hand, say 67, what are the odds of flopping four to a straight draw? How do the odds vary when the connector move apart from one another (68 as opposed to 67) and as the move closer to the 'edges' (AK, 34, et.)? I'm trying to figure the chances of cathcing either a straight or a flush by the river with with suited connectors starting.

BruceZ

06-30-2005, 07:17 AM

[ QUOTE ]
If you have two connectors in your hand, say 67, what are the odds of flopping four to a straight draw? How do the odds vary when the connector move apart from one another (68 as opposed to 67) and as the move closer to the 'edges' (AK, 34, et.)? I'm trying to figure the chances of cathcing either a straight or a flush by the river with with suited connectors starting.

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Suited connectors flop an 8-out straight draw 9.6% of the time. See this post (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2327858&page=&view=&s b=5&o=&vc=1) for how this changes near the edges, and for a link to the connector calculation.

EDITED 9/10/05 FROM:1-gappers from 53s-QTs flop 2/3 as many open-ended straight draws, and half the number of double gutshots, so they flop an 8-out straight draw 6.3% of the time.

EDITED 9/10/05 TO: 1-gappers from 53s-QTs flop 2/3 as many open-ended straight draws, only counting those for which we have 2 of the straight cards in our hand. 75s-T8s flop 3/2 as many double gutshots (3 vs. 2 for connectors), so they flop an 8-out straight draw 6.9% of the time. 53s,64s,J9s,QTs flop 2 double gutshots (same as connectors), so they flop an 8-out straight draw 6.6% of the time.

Suited connectors flop a gutshot draw 16.6% of the time. See this post (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2671508&page=&view=&s b=5&o=&vc=1) for the gutshot calculation. Removed 1-gapper gutshot calculation due to error 9/10/05.

maddog2030

06-30-2005, 09:58 AM

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Suited connectors flop a gutshot draw 17.9% of the time. See this post (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2671508&page=&view=&s b=5&o=&vc=1) for the gutshot calculation.

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Are you sure about the gutshot straight calculation? I've written a program to calculate every possible flop and every possible draw and it agrees with your open ended (9.6%) and open ended or flush draw (19.1%) calculations, but it disagrees with your gutshot calculation. I took a look at your calculations but didn't see anything that might exlain the discrepency. Maybe its my program, but it's odd that it got the other percentages correctly. Either way I'd like to figure it out.

Here is how it calculates it:

# Of Flops:
No Pair with Gutshot Straight and Flush and StraightFlush Draws: 120
No Pair with Gutshot Straight and Flush Draw: 222
No Pair with GutShot Straight: 2052

One Pair with Gutshot Straight and Flush and StraightFlush Draws: 72
One Pair with Gutshot Straight: 792

Total: 3258 flops or 16.62%

BruceZ

07-04-2005, 04:45 AM

[ QUOTE ]
[ QUOTE ]
Suited connectors flop a gut shot draw 17.9% of the time. See this post (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2671508&page=&view=&s b=5&o=&vc=1) for the gut shot calculation.

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Are you sure about the gutshot straight calculation? I've written a program to calculate every possible flop and every possible draw and it agrees with your open ended (9.6%) and open ended or flush draw (19.1%) calculations, but it disagrees with your gutshot calculation. I took a look at your calculations but didn't see anything that might exlain the discrepency. Maybe its my program, but it's odd that it got the other percentages correctly. Either way I'd like to figure it out.

Here is how it calculates it:

# Of Flops:
No Pair with Gutshot Straight and Flush and StraightFlush Draws: 120
No Pair with Gutshot Straight and Flush Draw: 222
No Pair with GutShot Straight: 2052

One Pair with Gutshot Straight and Flush and StraightFlush Draws: 72
One Pair with Gutshot Straight: 792

Total: 3258 flops or 16.62%

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It took me awhile to figure this out, but it was actually a simple problem. I was double counting (for JTs) the flops AK9, Q87, AQ8, and K97. The latter two are double gut shots which were subtracted, but only once. This explains why our totals differed by a factor of 63*4 = 252. I have corrected the original (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2671508&page=&view=&s b=5&o=&vc=1) calculation.

Note that your total number of gut shots with flush draws, 120 + 222 + 72 = 414, agrees with my 1866 - 1452 (http://archiveserver.twoplustwo.com/showthreaded.php?Cat=&Number=261078&page=&view=&sb =5&o=&vc=1) = 414. The 1866 is the number of clean flush draws including gut shots (9.5%), and 1452 is the number of clean flush draws excluding gut shots.

I also agree with your total number of gut shots with pairs, 72 + 792 = 864. This can be computed as:

6*(16*6 + 2*6*4) = 864.

That is, there are 6 pairs of ranks that can flop gut shots, times 16 ways to flop these ranks, times 6 ways to pair a hole card. 2*6*4 is the number of ways to pair the board for each of the 6 gut shots.

The 19.1% for the probability of flopping a flush or 8-out straight draw, and the 9.6% for flopping an 8-out straight draw, were originally computed by hand because of a disagreement with numbers posted by someone using Hold'em Analyzer software. This person later posted a hand calculation to support his numbers. His calculation was found to be in error, and my numbers were verified by several different people using different methods. We never figured out why the software result was wrong, though I knew it had to be. Now we have your software result to confirm my numbers, in addition to the hand calculations.

The gut shot calculation was done recently, and by only one method, so it was not as solid as the others. Now that it has been brought in line with the software result, we can have complete confidence in the 16.62% number for the probability of flopping a gut shot.

binions

07-07-2005, 09:00 AM

[ QUOTE ]
[ QUOTE ]
If you have two connectors in your hand, say 67, what are the odds of flopping four to a straight draw? How do the odds vary when the connector move apart from one another (68 as opposed to 67) and as the move closer to the 'edges' (AK, 34, et.)? I'm trying to figure the chances of cathcing either a straight or a flush by the river with with suited connectors starting.

[/ QUOTE ]

Suited connectors flop an 8-out straight draw 9.6% of the time. See this post (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2327858&page=&view=&s b=5&o=&vc=1) for how this changes near the edges, and for a link to the connector calculation. 1-gappers from 53s-QTs flop 2/3 as many open-ended straight draws, and half the number of double gutshots, so they flop an 8-out straight draw 6.3% of the time.

 EDITED FROM:
Suited connectors flop a gutshot draw 17.9% of the time. See this post (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2671508&page=&view=&s b=5&o=&vc=1) for the gutshot calculation. Modifying this for the 1-gappers 53s-QTs gives gutshots 5.6% of the time.

 EDITED TO:
Suited connectors flop a gutshot draw 16.6% of the time. See this post (http://forumserver.twoplustwo.com/showthreaded.php?Cat=&Number=2671508&page=&view=&s b=5&o=&vc=1) for the gutshot calculation. Modifying this for the 1-gappers 53s-QTs gives gutshots 5.3% of the time.

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The 9.6% and 6.3% of the time you flop an 8 out straight draw with 0 and 1-gap max stretch suited connectors, I assume you have excluded those flops in which you have flopped a flush. Correct? If so, then, for both 0- and 1-gap max stretch suited connectors:

1) how often does the flop come with a pair on the board ("paired") when you have an 8 out straight draw?

2) For those paired flops, how often will you flop a 4 flush along with an 8 out straight draw on a paired board?

3) How often will you flop 1 of your suit (a backdoor flush draw) with an 8 out straight draw on a paired, rainbow board?

4) How often will you flop 1 of your suit with an 8 out straight draw on a paired board with a 2 flush against you?

The rest of the questions deal with unpaired boards when you flop an 8 out straight draw:

5) how often does the flop come unpaired and give you a 4 flush?

6) how often does the flop come 3 of a suit against you?

7) how often does the flop come unpaired and 2 of a suit against you with none of your suit?

8) how often does the flop come unpaired and 2 of a suit against you with 1 of your suit (ie backdoor flush draw)

9) how often does the flop come unpaired and rainbow with none of your suit?

10) how often does the flop come unpaired and rainbow with 1 of your suit?

Finally, the 10.94% chance of flopping a 4 flush includes those times when you hold a 0- and 1-gap suited connector and flop an 8 out straight draw.

Therefore, I assume the chance of flopping an "clean" 8 out straight draw (without a 4 flush in your favor on an unpaired board that is also not 2 or 3 suited against you) is simply adding the chances of questions 9 and 10 above, correct?

Thanks a million.

maddog2030

07-07-2005, 09:05 AM

Look for my post in this forum a week or two back, it answers some of your questions. My program doesn't do backdoor flush draws but I could add that functionality fairly easily.