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Benford's Law

Definition

The empirical observation that in naturally occurring numerical data spanning multiple orders of magnitude, the leading digit d appears with probability log10(1 + 1/d), giving 1 a roughly 30.1% frequency and 9 a roughly 4.6% frequency.

Related terms

Chi-square test
A goodness-of-fit test comparing the observed digit frequencies in a dataset to the expected Benford frequencies, producing a test statistic that is...
Mean Absolute Deviation (MAD)
A practical Benford conformity measure that averages the absolute differences between observed and expected proportions across all leading digits, with Nigrini benchmarks...
Second-digit test
Analysis of the second significant digit in isolation, where 0 is expected to appear about 11.97% of the time. A spike in...
Two-digit test
An extension of Benford's Law to the first two significant digits, producing 90 possible combinations each with a predicted frequency, which is...
Z-statistic
A per-digit test that calculates whether the deviation between an observed frequency and the Benford expected frequency for that single digit is...

Explained in

  • Benford's Law and Digital AnalysisThe empirical observation that in naturally occurring numerical data spanning multiple orders of magnitude, the leading digit d appears with probability log10(...

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