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View Full Version : Checking some stuff re: RoR

DavidC
09-29-2005, 08:47 AM
Normal Distribution of Hourly Rate (http://archiveserver.twoplustwo.com/showthreaded.php?Cat=0&amp;Number=682745&amp;page=0)

[ QUOTE ]
Bankroll needed = -(standard deviation^2/2*avg, win per hour)ln(the risk you are willing to accept).

[/ QUOTE ]

Plugging in some numbers:

SD: 15 bb/100
WR: 2 bb/100
RoR: 0.1%

You'd need 388 bb....

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Questions:

1) Is this correct (the formula)?

2) Is this correct (the result)?

3) Can I use bb/100 and sd/100 in this formula?

Edit: At 1% Risk of Ruin, you'd only need 225 bb.

Edit: At 3.5 bb/100 and 0.1% RoR, you'd be looking again at requiring only 225 bb... So it obviously becomes much less risky as you have a higher winrate.

DavidC
09-29-2005, 09:09 AM
from some earlier post (http://archiveserver.twoplustwo.com/showflat.php?Cat=&amp;Board=genpok&amp;Number=207100&amp;fpart =&amp;PHPSESSID=)

Also, am I correct to assume that the two formulas are the same, just that one isolates B and the other isolates r?

B = -(sigma^2/2u)ln(r)
r = exp(-2uB/sigma^2)

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Is this the formula that I should be using?

DavidC
09-29-2005, 09:13 AM
[ QUOTE ]
from some earlier post (http://archiveserver.twoplustwo.com/showflat.php?Cat=&amp;Board=genpok&amp;Number=207100&amp;fpart =&amp;PHPSESSID=)

Also, am I correct to assume that the two formulas are the same, just that one isolates B and the other isolates r?

B = -(sigma^2/2u)ln(r)
r = exp(-2uB/sigma^2)

------

Is this the formula that I should be using?

[/ QUOTE ]

Okay, I'm laughing at myself now.

These are the same formula, with the exception of slightly different terminology and one being more compact since it's written in math symbols).

However, I'm glad I found the post still, because it had isolated for ROR instead of bankroll as well...

I guess these are correct... but someone please give me a "yep" if the third question is on the money too.

DavidC
09-29-2005, 01:50 PM
bump... #3 is the important one.

09-29-2005, 02:42 PM
Just want to point out that you may be the only poster in the history of 2+2 to reply to yourself three times before anyone else does. /images/graemlins/wink.gif Also wanted to save you from #4.