statistics
posted by maddy .
How do you calculate the degrees of freedom for unequal sample sizes and unequal variance (independent t test)

Degrees of freedom for unequal sample sizes and unequal variances =
(s1^2/n1 + s2^2/n2)^2

(s1^2/n1)^2/(n11) + (s2^2/n2)^2/(n21)
Note: ^2 means squared.
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