Suppose a measurement is made on some physical characteristic whose value is known, and let x denote the resulting measurement error. for an unbiased measuring instrument or technique, the mean value of x is 0. assume that any particular measurement error is normally distributed with variance s2 . let xn be a random sample of measurement errors.
(a) obtain the method of moments estimator of s2.
(b) obtain the maximum likelihood estimator of s2.