Variance of a distribution The distrilbution's variance is the rv,'s av, squared deviation from the mean var[w]=ow=2(ws-UW)"IS ariance measures the rvs variationVariance of a Distribution The distribution’s variance is the r.v.’s av. squared deviation from the mean; Variance measures the r.v.’s variation. var[w] w (w ) . s w s s S = = − =     2 2 1