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Empirical estimates

A simple empirical estimate of the probability distribution is obtained from a sample of data by calculating the relative frequency $ f_i=n_i/n$ of occurrence of each event $ \{X=x_i\}$. In the limit of large sample sizes, these empirical estimates $ \hat{p}(x_i)=f_i$ of the distribution provide increasingly accurate unbiased estimates of the population probabilty distribution. The empirical distribution can be displayed graphically by plotting bars of height $ f_i$ for the different values $ x_i$.



David Stephenson 2005-09-30