Why Multiply By 2?

R

rigor mortis

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People wonder why 2% was decided when applying the Rule of 2 and not any other number. There are 52 unknown cards, so the percentage of one card turning up is 1 in 52, or 1,923%. This was far too difficult a number to calculate your chances of winning in a game so it was rounded down to 50 unknown cards, giving an easier to remember number of 2%. While this is commendable for ease of use, in maths when you introduce rounding, either up or down you introduce errors. Waiting on the turn the error is 4% and the is same waiting for the river.
If you're happy with this error use the Rule

But please remember the error the next time you apply the rule!
 
Brandlad

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People wonder why 2% was decided when applying the Rule of 2 and not any other number. There are 52 unknown cards, so the percentage of one card turning up is 1 in 52, or 1,923%. This was far too difficult a number to calculate your chances of winning in a game so it was rounded down to 50 unknown cards, giving an easier to remember number of 2%. While this is commendable for ease of use, in maths when you introduce rounding, either up or down you introduce errors. Waiting on the turn the error is 4% and the is same waiting for the river.
If you're happy with this error use the Rule

But please remember the error the next time you apply the rule!


We can not use such a complicated method in online poker where clock runs out very fast.
Even in live poker it is very hard to focus after playing few hours and especially when lot of players are involved. So keep the math easy unless you are a real math pro.
 
eberetta1

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Yeah. I need to do that to improve my accuracy. Getting burned too many times on the river with that margin of error. What was that again? 0.0192307692. Silly me, why would I round to 2.
 
Cajin007

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Well, the rule of 2 is used post flop. After having made a 5 card hand, the rule is used to gauge the possibility of your hand improving, using the cards that help. The 2% is actually 0.021276( based on fact that after flop there are 47 unseen cards ).
The 4% rule ( 0.043015 ) is based only on if you will see both turn and river, to improve, and is based on combination of 1/47th plus 1/46th. ( after turn, 46 cards remain unseen ).
Remember this 2/4 rule was first created when computers were just coming out, and poker was more "live". Quick math, and tighter players made the calculations easier and more forgiving.
 
PaxMundi

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On the turn its x2+2 but that rarely gets mentioned because it usually confuses things.
 
ClickPoker

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Yesssssssssssssssss am very happy with this error.

Facilitate the calculation, They make you play more hands and winning more self-esteem you up When You take the right decision.

When you're learning to play, trust is very important, if you play with the greatest fear devour you. That simple calculation gives you security, safety take risks and win
 
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5pAce_C0wb0y

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People wonder why 2% was decided when applying the Rule of 2 and not any other number. There are 52 unknown cards, so the percentage of one card turning up is 1 in 52, or 1,923%. This was far too difficult a number to calculate your chances of winning in a game so it was rounded down to 50 unknown cards, giving an easier to remember number of 2%. While this is commendable for ease of use, in maths when you introduce rounding, either up or down you introduce errors. Waiting on the turn the error is 4% and the is same waiting for the river.
If you're happy with this error use the Rule

But please remember the error the next time you apply the rule!


Just a quick one. I'm not making any decision until there are 2 cards in my hand. There are then 50 unknown cards and the 2% is accurate.
 
R

rigor mortis

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eberetta - indeed you are a legend, unfortunately it is only in your own mind, Sarcasm they say is the lowest form of wit and it suits you down to the ground. There's no point in reiterating the rationale of my post to someone who is mentally challenged.
 
R

rigor mortis

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Just a quick one. I'm not making any decision until there are 2 cards in my hand. There are then 50 unknown cards and the 2% is accurate.
Sorry COwbOy, but the Rule of 2 only comes into consideration after the flop, (where there are now 47 unknown cards), and the times 2 applies
 
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5pAce_C0wb0y

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Sorry COwbOy, but the Rule of 2 only comes into consideration after the flop, (where there are now 47 unknown cards), and the times 2 applies


You miss my point. In your original post you say about 52 unknown cards and its rounded down to 50 for easy maths. Its rounded down to 50 cos 2 cards are in your hand.
 
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