Online bankroll management

[pzhon]

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I just read an interesting book on cash management called: Fortune's formula by William Poundstone. It discusses many things, but the relevant topic is the 'Kelly Criterion" .


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The simple guideline I gave in the linked post, bankroll = comfort * standard deviation^2 / win rate, is closely related to the Kelly criterion. Comfort is the inverse of the Kelly fraction.

Most people find the swings you will experience by using the Kelly criterion to be too large. Most people prefer using fractional Kelly system which gives you almost as much growth for substantially reduced swings. So, you can use the pure Kelly criterion if you want, but note that many people have cause for rejecting it.

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Essentially, you always bet a percentage of your stake. ie 10%.

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No, not when you are presented with several wagers with different returns. You should not assume that your win rate is the same no matter what level you play.

What Kelly wrote, in the first paper on the subject, is far beyond the simplifications most people attribute to him. When people look for generalizations of the Kelly criterion, they often are working to rediscover what Kelly put in that first paper.

[HoldenFoldem]

Thanks for your input on this. I interpreted it to mean you would buy in to a game of NL and put 10% of your stake on the table as your buy in. If you lost it, you would next put 10% of your remaining 90% on the table as your next buy in and so on.

The difficulty with the formula in my view is that you must estimate your "edge", as he defined it, to determine your optimum bets. I have no idea how you would do that at poker. Perhaps BBs per hundred hands. But lets say that you win 8 BB per hundred hands, now how would you use that information to determine your buy in amount, and your subsequent bet sizes while sitting at the table.

Perhaps, assuming AA dealt to you, and using Poker Stove to determine your chances of winning with 2 callers, and assuming poker stove says 45% chance of winning, you would want to put no more than 45% of your stack in the pot.

With 10,9 suited and a 8% chance of winning, no more than 8% of your buy in would go in to the pot.

I am only theorizing here, and would appreciate any input from those much more mathematically able.

[pzhon]

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Thanks for your input on this. I interpreted it to mean you would buy in to a game of NL and put 10% of your stake on the table as your buy in.

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Your interpretation is wrong. Buying in for 1/2 of a stack does not cut your swings in half. It is like using half of a tank of gas--your mileage does not go down much due to the decreased weight. In addition, when you buy in short, you may change your win rate dramatically (possibly turning yourself into a winning player, but also possibly cutting your win rate signficantly).

Buying in for 10% of your $250 bankroll at a NL $100 table is very different from buying in for 10% of your bankroll at a NL $25 table.

In case you are interested in a rational approach to bankroll management, and are unable to translate the Kelly criterion to the poker context yourself, you may want to read and think about what I posted in the Beginners Questions forum.

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Perhaps, assuming AA dealt to you, and using Poker Stove to determine your chances of winning with 2 callers, and assuming poker stove says 45% chance of winning, you would want to put no more than 45% of your stack in the pot.


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This is really confused. It sounds like you are going to throw away any edge you might have, and then blame the resulting disaster on bankroll management. When you have AA, you should have no qualms about putting your whole stack in preflop as long as you didn't buy in for almost all of your bankroll.

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I am only theorizing here, and would appreciate any input from those much more mathematically able.

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Please read what I wrote.