What is stdv (or standard deviation)?
Short Answer: Basically it is a measure of variance. The bigger the stdv, the bigger your swings are. Long Answer: If you assume that your performance is normal (looks like a bell curve) then, 68% of your samples will fall within one standard deviation of the mean. About 95% will be within two standard deviations of the mean. For example, if your average hourly rate is +$10 and your standard deviation is ±$50, then 68% of your hours will be between -$40 and +$60 . Please Note: the stdv value in the charts is only an estimate of your “true” standard deviation. The more sessions you have, the more accurate this estimate should be. I use a weighted standard deviation, which means I take into account the length of the sessions when I calculate standard deviation. Also, as with all the statistics generated on this website, your past performance is NOT a guarantee of future performance. Future performance can be affected by other factors, including, but not limited to, changes in your playin
