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LetYouDown
12-01-2005, 12:32 PM
Started a new PT database maybe a month ago. After ~16,000 hands I have a SD of 51BB/100. Does this indicate anything, in and of itself?

danzasmack
12-01-2005, 01:44 PM
I may not be 100% correct here but...

You have a sample of data which you use to calculate a statistic - BB/100

Let us assume you BB/100 = 2.0 for simplicity.

Now, a question on this forum is very often "am i a winning player?" The SD/100 can help us calculate it.

We want to estimate the mean so we will use SE of the Mean, which in this case = (SD/100)/(n^.5)= 51/(16000^.5) = .40 (about)

So, for 99% confidence interval we do 3 SD's from the mean, so we are 99% sure that your TRUE BB/100 is in the interval [.8, 3.2]

(assuming your BB/100 is 2)

12-01-2005, 01:57 PM
This is wrong. In particular the N you should use is the measurement unit (100 hands, or 160). The 99% confidence interval is 10.38 BB on both sides.

Fifty-one is a very large SD for limit. I don't know about NL. Are you sure you got it from Pokertracker correctly?

danzasmack
12-01-2005, 02:26 PM
I knew that didn't seem right - thanks

LetYouDown
12-01-2005, 02:31 PM
I'm playing NL and I went to the Summary tab and hit more detail. That's what it displayed for ~16000 hands.

12-01-2005, 06:08 PM
That's how I get my SD. I suppose 51 is possible. I don't know whats reasonable in NL. You may get a better response on a NL board.

pzhon
12-02-2005, 06:02 AM
[ QUOTE ]
Started a new PT database maybe a month ago. After ~16,000 hands I have a SD of 51BB/100. Does this indicate anything, in and of itself?

[/ QUOTE ]
Not really. I think anything between 30 PTBB/100 and 70 PTBB/100 is normal for NL.