This is a discussion on Rule of 2 within the online poker forums, in the Learning Poker section; Phil Gordon was the first to coin "Rule of 2 and 4", where you multiplied our outs by 4 on the turn and by 2
Phil Gordon was the first to coin "Rule of 2 and 4", where you multiplied our outs by 4 on the turn and by 2 on the river. Multiplying by 4 appears to be on the wane, probably because of the huge margins of error .Example : you have 15 outs and multiply these by 4 giving you a 605 chance to win. 605 equates to 0.67/1 against 2,07/1 true odds.
A Rule of 2 (and occasionally 4) evolved to overcome this problem.
You multiply your turn odds by 2. You multiply your river outs by 2 and multiply your turn outs by 4 if opponent goes all-in on the flop.
However even this has its shortcomings as will be shown
Outs X2 Odds to 1 True Turn odds True River odds
3 6% 15.67 14.67% 14.33%
6 12% 7.33 6.83 6.67
9 18% 4.55 4.22 4.11
12 24% 3.17 2.92 2.83
15 30% 2.33 2.13 2.07
18 36% 1.78 1.61 1.55
21 42% 1.38 1.24 1.19
A B C
Although on face value these figures appear acceptable, and they are after all approximate values, they do have their flaws.
Outs % Error on % Error on
Turn, A & B River, A & C
3 6.82 9.35
6 7.32 9.89
9 7.82 10.70
12 8.56 12.01
15 9.39 12.56
18 10.56 14.84
21 11.29 15.97
All figures are to two decimal places, rounded. column A is the percentages converted to a ratio.
If you are happy to use the rule of 2 with the errors shown, carry on. All I'm pointing out are the errors.
I have no idea where some of your conclusions came from.
15 outs times 4 is 60%
Actual odds: 54.4% (give or take with actual cards)
That is a little better than 1:1 not 2:1.
The rule of 4 has its shortcomings, primarily when you have a lot of outs, but it isn't wildly inaccurate. It is usually good enough given that you don't have perfect knowledge of your opponent's hand and what cards are live/dead.
Now, multiplying by 4 is not encouraged. Using the rule of 2 is encouraged, mostly because you might be facing further action. You may not see the river because of a large turn bet. So, when the flop bet doesn't put you all-in, use the rule of 2 unless you are sure you will commit to any bet on the turn anyway. If you are going to be all-in or not fold the turn bet, then use the rule of 4.
I get no respect. When I move all-in, people from other tables call.
First of all, I'm pretty sure Phil Gordon didn't come up with the "Rule of 4 and 2", though a lot of people probably encountered it for the first time back in the day in his Little Green Book.
Second, we had this exact same discussion a few months ago and I still don't think you understand how the guideline is supposed to be applied. Here's the previous version if anyone wants to check it out before going over old ground again: https://www.cardschat.com/forum/lear...ur-two-326009/
Third if you want something to display as a table, do it in Excel or Word or something then screenshot it and upload it as an image (see the one one I uploaded in the previous thread as an example).
We need Chemist to come back in here quoting Hitchiker's Guide again methinks. It worked last time :P
Sure, 15 x 4 = 60%, which is a bit off from the actual 54% you're actually getting, but that's a pretty minor detail as it's pretty much an instant call getting better than 50% odds to win a hand.
Here is what you seem to fail to understand: the rule of 2 and 4 is a way to get a quick estimate of the percentage chance your hand has to win. That's it, it's a quick guide-nothing exactly 100% but a fast mathematical method to get close enough.
If you want, in some parts, you can +n/-n after some of the x2/x4 to get a bit closer to the actual percentage.
The way it is applied is meant to be a quick and easy way to see if you're getting the proper odds to call a bet. Lets say, for example, I have 9 outs for flush:
9 x 2 = 18 or a ~18% chance to win. Actual odds is 19.1%
Opponent bets $30 into a $90 pot. I have to call $30 to win $120. $30 is 25% of $120, so the pot odds is 25%
I know 25% pot odds > 18% hand odds, so it's an easy fold.
I did not need to know the exact 19.1% hand odds in order to make this decision.
The rule of 2 and 4 is a guide and nothing more. For more accurate hand odds v pot odds, do the ratio method, but do them correctly. Both method works, but be sure you're doing them correctly when it comes to comparing hand/pot odds and when you need to call/fold. For example, don't do percentage method for hands odds, ratio for pot odds unless you can convert one of them into the other. Ratio: Pot odds > Hand odds = Call. Percentage = Hand Percentage > Pot Percentage = Call
I am one of these people who is very bad with numbers but brilliant with actual logic itself.
I picture four columns in front of me (suits) and 13 rows (card types) then I imagine the outs lighting up for me and combo-ults light dimmer while the singular outs shine bright. This helps me with turn odds and river odds. This is all I need to do to completely comprehend what proportion of cards that CAN come up on the turn and/or river will help me, draw me dead or cooler me.