What is the mathematical formula for the pooled variance of two populations?

Jefferson Booth 2022-11-18 Answered
What is the mathematical formula for the pooled variance of two populations?
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Answers (1)

Kaeden Lara
Answered 2022-11-19 Author has 23 answers
The pooled standard deviation is given by
S p = ( n 1 - 1 ) s 1 2 + ( n 2 - 1 ) s 2 2 n 1 + n 2 - 2
for variance remove the sqare root operator
V p = ( n 1 - 1 ) s 1 2 + ( n 2 - 1 ) s 2 2 n 1 + n 2 - 2
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