Dears, The kurtosis consists of the 4th central moment and the square of variance. It measures the peakedness of the distribution. However, it is hard to understand why 4th central moment is used to measure 'peakedness' of the distribution. What is the 4-th central moment? It looks similar to the variance (2nd central moment). However, 2nd central moment represents the dispersion, and 4th central moment does the shape of the distribuion. What is the difference between 2nd and 4th central moments? Thanks.