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Old 10-10-2007, 03:51 AM
Josem Josem is offline
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Join Date: Jan 2007
Location: Victoria, Australia
Posts: 4,780
Default Re: Latest cliffsnotes on Absolute soulreading.

OK.

I've just read the wikipedia entry on standard deviation, and am more convinced than ever before that flight2q has no idea what a standard deviation is.

The idea of calculating a standard deviation on a single result from 190 hands is absurd.

A standard deviation is a measure of a spread of results. Inherently, a single result obviously can't be spread.


So, I took the bb/100 data in excel, and firstly found the mean of the 5251 results. The mean was -4.0493. That is, of the 5,251 players who played over 500 hands, they lost on average 4bb/100.

I then used MS Excel's STDEVA function to calculate the standard devation of that same sample ('cause I certainly wasn't doing 5,000+ calcs by hand!) and it reported that there was a standard deviation of 31.54.

Now, the cheater's BB/100 was 475.74. That is a whopping 15.2 standard deviations from the mean.

To put that into perspective, Wikipedia lists confidence intervals for standard distributions that assume normally distributed data:

σ 68.26894921371%
2σ 95.44997361036%
3σ 99.73002039367%
4σ 99.99366575163%
5σ 99.99994266969%
6σ 99.99999980268%
7σ 99.99999999974%

They don't even bother going past 7 standard deviations because of how rare such occurences are.
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