# statistics

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How do you calculate the degrees of freedom for unequal sample sizes and unequal variance (independent t test)

• statistics -

Degrees of freedom for unequal sample sizes and unequal variances =

(s1^2/n1 + s2^2/n2)^2
-----------------------------
(s1^2/n1)^2/(n1-1) + (s2^2/n2)^2/(n2-1)

Note: ^2 means squared.

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