This means we end up with a population variance of 130.67 and sample variance of 156.8. To figure out the standard deviation, we have to take the square root of the variance, which is 11.43 ...

Most projects aren't as simple as hiring one contractor to build a deck. In most cases, project managers rely on a formula to calculate schedule variance.

This paper gives alternative derivations for the standard variance formulas in two-stage sampling. The derivations are based on a direct use of the statistical properties of the sampling errors in the ...