[King Yao]

Hi Binion, thanks for responding. I hope you don’t think I am questioning you. I just want to get to the bottom of possible differences, and I want to make sure I didn’t screw up something in my book. That wouldn’t be good. I would appreciate it if you could please take a look at this and let me know what you think.

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Do you agree a backdoor flush draw is 23:1 to hit? 10/47 * 9/46 = 4.16% which is 23:1 against.


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Yes, I agree with this.

I'm going to go through an example using DIPO because I think it will illustrate how the way I count outs works in accordance with DIPO. It is possible the number of outs may not work using other methods (maybe it is a case of mixing and matching different definitions). I haven't thought about using other methods since I don't use them, so if there is an inconsistency after the definitions are adjusted accordingly, please let me know.

Just to summarize the DIPO method for those that are unaware of it :
Good Number: Expected Outs x Expected Pot Size
Bad Number: Expected Non-Outs (also known as Unknown Cards minus Expected Outs)

If Good Number is greater than Bad Number, then you have pot odds to call.

Let's assume you have suited cards in your hand, and the Flop has one card of your suit. Let's assume you know for a fact that your backdoor flush will be good if you hit, but you have no other outs.

You estimate 10/47 x 9 as your expected outs and use 1.91 as the expected outs. And then you try to see how big you need the expected pot size to be in order for you to call. (note in DIPO, I suggest that you only count the bets accumulated on the Turn, but not all the way to the River as a way of estimation – and it is just that, just a quick estimation at the table)

Expected Outs = 1.91
Expected Non-Outs = 45.09

This means the Expected Pot Size must be greater than 23.6 small bets in order for a call to be correct.

1.91 x 23.6 = 45.1

So DIPO is saying you can call if you have greater than 23.5 to 1. That sounds fairly close to what you are claiming (22.5 to 1). I recommend rounding to either 2, 1.5 or 1 out. 2 for the highest backdoor flush draw (a little bit of the possibility of getting a ton of bets if someone else also has a backdoor flush draw – but more because it is easier to use 2 than 1.9 in your head). 1.5 for the 2nd and 3rd highest flush draws (lower than 1.9) and 1 for all other backdoor flush draws (to account for the times you get smacked down against another flush draw).

This recommendation is a quick and dirty estimation to add to the outs….I feel if using DIPO, it is fairly accurate.

I've got a head-ache now. Can't believe I did this on a Friday night, I guess that shows my lifestyle, eh? [img]/images/graemlins/ooo.gif[/img]