Standard Deviation

Another important measure is your standard deviation. Without getting too
technical, this measures the fluctuations you can expect in your play. Aggressive
players who play a lot of hands can expect greater variances than a tight player
docs. The aggressive loose player will lose a lot most of the time and occasionally
experience a big win, while a tight conservative player will not have huge swings
either way. The higher your standard deviation, the more bankroll you need to
handle the fluctuations in your results.
Calculating your standard deviation is outside the scope of this site. If you use
staffing to track your results, the software will calculate your standard deviation for
you. For those who want more information on earn rate and standard deviation.
Mason Malmuth provides all of the formulas in his book Gambling Theory and Other Topics.
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