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Old December 12th, 2008, 01:20 PM
dudders dudders is offline
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Default que about standard deviation.

i have been reading about standard deviation and most sites seem to say 1.21 is about the avg? is this true..? aslo what formula do i use to figure out what my expected loss or gains will be over a span of hours or number of hands i play. im fairly new at this so i appologize for my stupidity.

thanx!
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Old December 12th, 2008, 02:57 PM
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FLASH1296 FLASH1296 is offline
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The exact figure will depend on the game.
In any case, I always think of the S.D. as 1.11
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Old December 12th, 2008, 03:11 PM
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Sonny Sonny is offline
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As Flash said, your win rate will vary based on the game and your playing style. The best way to get a more accurate number is to use computer simulation software to mimic your game and style. After the computer has played a few billion hands you will have a good idea of what sort of advantage you are playing with.

The variance for a single hand of BJ is around 1.33 squared units, which gives a standard deviation of about 1.15 units. Those are just generic numbers for flat betting though. A computer sim will give you a more accurate number for your specific style of play.

You can also estimate your advantage based on the advantages listed in various card counting books, but those may not accurately reflect the way that you play.

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Old December 12th, 2008, 10:36 PM
Kasi Kasi is offline
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Quote:
Originally Posted by dudders View Post
i have been reading about standard deviation and most sites seem to say 1.21 is about the avg? is this true..? aslo what formula do i use to figure out what my expected loss or gains will be over a span of hours or number of hands i play. im fairly new at this so i appologize for my stupidity. thanx!
First of all, it's not stupidity. Don't even think that about yourself. I don't think that about you and never will. Don't confuse ignorance with stupidity. And never apologize for trying to learn something new.

That said, lol, it's kind of a Catch 22 assuming you are varying your bet. If you know your EV and SD per round, the formulas are easy to apply. To be accurate about them, you need a sim. If you have a sim, you won't have to really worry about the formulas lol.

If you vary your bet, throw out that 1.15. An AP's SD/rd will almost always be higher, sometimes many times higher. SD mostly depends on how often you bet how much. The advantage you may have when you bet whatever will not effect your SD.

Likewise EV depends on how much you bet how often at what advantage.
Whatever it is per round, it is. Play a thousand rounds, multiply by 1000 lol.
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