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 Rolen 12-25-2005 08:23 AM

Risk of ruin

With a \$5K bankroll, winrate of 3BB/100 hands and SD of 80BB/100 hands, What's my ROR playing \$1/2?

What if my winrate is 0.5BB/100?

 ohnonotthat 12-25-2005 09:26 AM

Huh ?

A 3BB/100 win rate with a SD of EIGHTY BIG BETS PER 100 HANDS ?

Agression is good but the fact that "call" is a four-letter word does not make it an obscene play.

An 80BB/100 SD is all but impossible for a winning player - for that matter I'm not sure a LOSING player could manage this trick; there are, after all, a limited number of opportunities to shove chips into the pot.

*

There is no realistic chance that a 3BB/100 winner could ever go through 2,500 big bets even with an SD this large.

Your ROR with this WR and SD would be negligible with a stake of ONE thousand dollars and bear in mind mutiplying your stake by 5 does not reduce your ROR by 80%; it reduces it by upwards of 99%.

If this is merely an academic question I'll let someone else explain the formula for calculating ROR.

If these are your real figures you might want to get a script for Valium; if this is not possible you might want to consider drinking heavily during your sessions.

Please see the receptionist on the way out and no, we do not validate.

 BruceZ 12-25-2005 09:29 PM

Re: Huh ?

[ QUOTE ]
A 3BB/100 win rate with a SD of EIGHTY BIG BETS PER 100 HANDS ?To answer your question . . .

There is no realistic chance that a 3BB/100 winner could ever go through 2,500 big bets even with an SD this large.

[/ QUOTE ]

False. ROR = exp(-2*3*2500/80^2) =~ 9.6%.

[ QUOTE ]
Your ROR with this WR and SD would be negligible with a stake of ONE thousand dollars

[/ QUOTE ]

False. ROR = exp(-2*3*500/80^2) = 62.6%.

[ QUOTE ]
and bear in mind mutiplying your stake by 5 does not reduce your ROR by 80%; it reduces it by upwards of 99%.

[/ QUOTE ]

It raises it to the 5th power to (62.6%)^5 = 9.6%, which is a reduction of about 85% from 62.6%.

[ QUOTE ]
If this is merely an academic question I'll let someone else explain the formula for calculating ROR.

[/ QUOTE ]

Bankroll Formulas

Derivation of bankroll formulas

Online calculators for bankroll and risk of ruin

 ohnonotthat 12-25-2005 10:47 PM

Re: Huh ?

I stand corrected.

Question: Am I correct that only maniac on amphetamines could maintain such a SD (80 BB/100hands) and that even this maniac would have to work amazingly hard to do so ?

P.S. I'm aware that these figures have been created by some of the finest minds of our times (no sarcasm intended) but I need to see/hear about some empirical results before I can accept as gospel the idea that a \$6/100 hand winner has almost a 10% chance of blowing through 5k - even with a SD this high.

That said, I appreciate your input.

I am somewhat under-educated in this area since almost from day #1 I was fortunate enough to never have had to worry about ROR.

I am aware, however, that this fact is not a legitimate excuse for making off the cuff (and apparently incorrect) statements.

- I've also never had malaria but I wouldn't make glib, poorly thought-out remark in regard to the value of quinine.

(nodding in shame)

Thanks,

- Chris

 Izverg04 12-26-2005 12:02 AM

Re: Huh ?

[ QUOTE ]

Question: Am I correct that only maniac on amphetamines could maintain such a SD (80 BB/100hands) and that even this maniac would have to work amazingly hard to do so ?

[/ QUOTE ]
Think what your SD/hand will be if you only use the raise button (no checks, calls or folds on any street). If your opponents are not as crazy, the pot size will typically be around 20 BB, I guess, with around 7 BB coming from you. In this wildest case scenario, your SD/hand will be still smaller than 8 BB, so SD of 80 BB/100 is not possible unless your opponents play along.

 ohnonotthat 12-26-2005 12:52 AM

Re: Huh ?

That's what I thought.

This was my thinking re. a 3BB/100 winner burning through 5k playing 1-2.

Theoretically possible but in practice bordering on tossing a coin and having it land on its edge - 3 times in a row.

-

Thanks for clarfying this.

- Chris

 Rolen 12-26-2005 06:28 PM

Re: Huh ?

It's called shorthanded NL!

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