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  #11  
Old May 5th, 2011, 02:11 PM
Midwestern Midwestern is offline
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Quote:
Originally Posted by kewljason View Post
With Kelly if you keep resizing downword, you will not be resizing your entire spread as most likely the minimum wager is set by table minimums, so you are resizing your top wager and reducing your spread. this makes it more difficult to recoup earlier losses. Imagine trying to win back losses acheived with a $10-$100 spread when kelly resizing has now reduced your spread to $10-$50.
I like this idea alot though for long-term bankroll growth. By figuring out whatever kelly bet we would do at different TC (i.e. the betramp i figured out earlier)

As the bankroll grows, the size of your bets grow when you have advantage, but at lower TC situations, Kelly still calls for minimum bets.

Basically this means you increase/decrease your spread proportionally according to your bankroll growth.

KJ, that means that even though you play 25-400, you should try playing 5-400, beacuse you are probably overbetting in some low-edge scenarios. I can see you getting away with this by betting 25 off the top of a shoe (so a PB eyes you as a $25 player and still thinks you spread 1-16), but scale it down little by little so that you're betting 5 if the count isnt fully TC+1. This increases your true spread to 1-80 which sounds to me like a very powerful game.
  #12  
Old May 21st, 2011, 07:44 PM
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blackjack avenger blackjack avenger is offline
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Default Conservative Kelly Resizing Wins

Betting .5 kelly has the same growth rate as 1.5 kelly but the former has far less variance.

Betting double kelly the bank meanders up and down.

Betting over double kelly your bank shrinks.

Given the above it's probably best to be sure to always bet less then kelly.

Probably way less then kelly if you have a large bank.
  #13  
Old May 21st, 2011, 08:02 PM
tthree tthree is offline
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The big rolls I talk to like 1/4 kelly.
  #14  
Old June 25th, 2011, 08:35 AM
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Default terminology

Fixed ror is just that. A 1% ror means you have a 1 in 100 chance of losing all.

In theory Kelly continuous resizing does not lose all, but in the real world one can lose so much they cannot play due to table minimums. Also, we are not sure of our advantage and Kelly punishes for overbetting. With smaller banks half Kelly may be reasonable with larger banks using third to fourth Kelly. The more important bank preservation the more conservative the bets.
  #15  
Old September 16th, 2011, 05:47 AM
Mersenne Twister Mersenne Twister is offline
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To predict the magnitude of fluctuation,
I recommend this book,

“An introduction to stochastic modeling Third Edition ”
by Samuel Karlin, Howard M. Taylor

It's better than Don's BJA3.
  #16  
Old September 16th, 2011, 09:04 AM
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Default theory vs reality

Quote:
Originally Posted by tthree View Post
The big rolls I talk to like 1/4 kelly.
.992 for 1/4
.998 for 1/5
Chance of never losing half with continuous resizing. So in theory 1/5 does not give much more safety. In the real world risk of drawdown is probably higher due to human error.

A problem with 1/4 is you still may have to resize down on losses which raises N0. At 1/8 + Kelly, resizing is less of an issue, which some pros use.

Last edited by blackjack avenger; September 16th, 2011 at 10:32 AM. Reason: error
  #17  
Old September 16th, 2011, 10:18 AM
Mersenne Twister Mersenne Twister is offline
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Quote:
Originally Posted by blackjack avenger View Post
.2 for 1/4
.8 for 1/5
Chance of losing half with continuous resizing. So in theory 1/5 does not give much more safety. In the real world risk of drawdown is probably higher due to human error.

A problem with 1/4 is you still may have to resize down on losses which raises N0. At 1/8 + Kelly resizing is less of an issue, which some pros use.

"Chance of losing half with continuous resizing" is
0.78125% for 1/4 Kelly
0.1953125% for 1/5 Kelly
  #18  
Old September 16th, 2011, 10:25 AM
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Default thanx

Quote:
Originally Posted by Mersenne Twister View Post
"Chance of losing half with continuous resizing" is
0.78125% for 1/4 Kelly
0.1953125% for 1/5 Kelly
For catching my error in text. I believe I fixed it. On your numbers, well yeah if you want to get precise!

Last edited by blackjack avenger; September 16th, 2011 at 10:28 AM.
 

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