Do you want a pooled standard deviation or a total standard devation? One
ignores mean differences, the other does not.
At 01:01 PM 5/17/01 +0200, Nasser Hosseini wrote:
>Hi everybody!
>
>I wonder, if anybody out there knows, how to calculate the "mean" Standard
>deviation, if you have a number of Mean and Standard deviation based on
>DIFFERENT number of measurment:
>
>Subject 1: N1 (no. of measurment), M1 (mean), S1 (Standard deviation)
>Subject 2: N2 , M2 , S2
>...
>Subject m: Nm , M2 , Sm
>
>i.e. Stotal = F(S1,S2,...,Sm; N1,N2,...,Nm)???
>
>Thanks
>
>/Nasser Hosseini
>
>
>
>
>
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------------------------------------
Paul R. Swank, PhD.
Professor
UT-Houston School of Nursing
Center for Nursing Research
Phone (713)500-2031
Fax (713) 500-2033
soon to be moving to the Department of Pediatrics
UT Houston School of Medicine
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