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Nottom
10-11-2003, 09:53 PM
can somebody post (or point me to another post with) the formula for knowing how accurate your winrate is based on hours played, SD and all that jazz.

BruceZ
10-12-2003, 03:17 AM
can somebody post (or point me to another post with) the formula for knowing how accurate your winrate is based on hours played, SD and all that jazz.

Simply divide your SD by the square root of the number of hours played. That's all, no jazz. /images/graemlins/cool.gif That's the standard error of your hourly rate.

Standard error works just like a standard deviation, i.e., your true EV will lie within +/- 1 standard errors of your hourly rate with 68% confidence, +/- 2 standard errors with 95% confidence, etc. A couple other ones you may want to know are that +/- 1.6 standard errors corresponds to 90% confidence, and +/- 1.3 standard errors corresponds to 80% confidence.

For example, if your SD is 10 bb for 1 hour, and you play for 400 hours, then the standard error of your hourly rate is 10/sqrt(400) = 0.5 bb/hr. So your hourly rate will be accuarate to within +/- 0.5 bb/hr with 68% confidence. It will be accuarate to within +/- 1 bb/hr with 95% confidence.

Notice that if your SD is 10 times your true hourly rate, then in order to be 90% confident that your hourly rate is accurate to within 10%, you would have to play 25,600 hours, which is about 13 years of full time play.

Nottom
10-12-2003, 04:22 PM
Thanks BruceZ. I was hoping you would notice my post. /images/graemlins/smile.gif