Question
The formula for the pooled variance, $s_{p}^{2},$ is given on page $440 .$ Show that, if the sample sizes, $n_{1}$ and $n_{2},$ are equal, then $s_{p}^{2}$ is the mean of $s_{1}^{2}$ and $s_{2}^{2}$
Step 1
Step 1: The formula for the pooled variance, $s_{p}^{2}$, is given by: \[s_{p}^{2} = \frac{(n_{1}-1)s_{1}^{2} + (n_{2}-1)s_{2}^{2}}{n_{1}+n_{2}-2}\] Show more…
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