The rth sample raw moment m_r^, of a sample with sample size n is defined as m_r^, = 1/n sum_(k = 1)^n x_k^r. The sample raw moments are unbiased estimators of the population raw moments, 〈m_r^, 〉 = μ_r^, . (Rose and Smith 2002, p. 253). The sample raw moment m_r^, is related to power sums S_r by m_r^, = S_r/n.