Question

# Assume the sample is from a normally distributed population and construct the indicated confidence intervals for (a) the population variance σ^{2} and

Confidence intervals

Assume the sample is from a normally distributed population and construct the indicated confidence intervals for (a) the population variance $$\displaystyleσ^{{{2}}}$$ and (b) the population standard deviation σσ. Interpret the results. The diameters (in inches) of 18 randomly selected bolts produced by a machine are listed. Use a 95% level of confidence.
4.477 4.425 4.034 4.317 4.003 3.760 3.818 3.749 4.240 3.941 4.131 4.545 3.958 3.741 3.859 3.816 4.448 4.206