anyone know what the "pooled standard error" is??
2007-12-10 05:22:14 · 2 answers · asked by Amanda 1 in Science & Mathematics ➔ Mathematics
Pooled standard error is the square root of the arithmetic average of the variances of the samples.
There is a very strong requirement that in expectation all variances are equal. Essentially this means that all regressors are orthogonal and all samples are truly independent.
2007-12-13 15:53:20 · answer #1 · answered by OPM 7 · 0⤊ 0⤋
This is the standard error when combining samples.
Use this formula when the population standard deviations are unknown, but assumed to be equal; and the samples sizes (n1) and (n2) are small (under 30).
SEpooled = sqrt{ [ (n1 -1) * s12) + (n1 -1) * s12) ] / ((n1 + n1 -1) } where Ï1 = Ï2
2007-12-12 15:17:16 · answer #2 · answered by Leltos 5 · 0⤊ 0⤋