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  • William Hogan thinks this is interesting:

The Z-statistic is used to test whether the actual proportion for a specific first-two digit combination differs significantly from the expectation of Benford's Law. The formula takes into account the absolute magnitude of the difference (the numeric distance from the actual to the expected), the size of the data set, and the magnitude of the expected proportion. The formula adapted from Fleiss (1981) is shown in Equation 6.1:

(6.1) equation