Question

An experiment involves selecting a random sample of 256 middle managers at random for study. one item of interest is their mean annual income. the sample mean is computed to be $35,420 and the sample standard deviation is $2,050. what is the standard error of the mean?

Answer 1

The standard error of the mean is 128.125.

The formula for standard error is:

$\sigma_M=\frac{\sigma}{\sqrt{N}}$

With our information, we have:

$\sigma_M=\frac{2050}{\sqrt{256}}=128.125.$