Standard Deviation?

[mikewvp]

So I have my standard deviation, but I don't exactly understand its significance. Anyone care to let me know?

[uuDevil]

Very roughly, it is a measure of the difference between how you do in a good hour of play versus a bad hour.

More precisely, it tells you that in a given hour (or other unit) of play, about 2/3 of the time, you will win your average win rate plus or minus 1 standard deviation.

Example: If my win rate is 1 BB/hr and my SD is 15 BB/hr, 2/3 of the time I will win between 16 BB and -15 BB.

These are the two most important things you usually want to know about a distribution (like your poker results): a measure of central tendency or "average," and a measure of dispersion or "spread" (like standard deviation).