What is pooled standard deviation and how is it calculated ?

Janiya Rose 2022-08-12 Answered
What is pooled standard deviation and how is it calculated ?
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Kaitlynn Church
Answered 2022-08-13 Author has 19 answers
The pooled standard deviation is weighted mean/average of standard deviations for two or more independent groups of data.
The pooled standard deviation is calculated by using the following equation :
S p = i = 1 k ( n 1 1 ) s i 2 i = 1 k ( n 1 1 )
where n i represents the sample size of the i-th group, while the s i 2 represents the variance of the i-th group and k represents the number of groups.
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