where the law came from
simon newcomb
a canadian-american astronomer at the naval observatory, working out of a shared book of logarithm tables. the early pages were grey with use and the later ones were clean, and he took that as evidence rather than wear. he published two pages, gave the frequencies for the first and second digit, offered a short argument for why, and moved on. nobody followed it up.
note on the frequency of use of the different digits in natural numbers. american journal of mathematics 4(1), 1881, pp. 39–40read the two pages →frank benford
a physicist at general electric who found the same pattern fifty-seven years later without knowing newcomb had. he did the part newcomb skipped: 20,229 numbers from twenty unrelated tables, rivers and populations and atomic weights and street addresses and newspaper figures. the distribution held in all of them, and the law took his name.
the law of anomalous numbers. proceedings of the american philosophical society 78(4), 1938, pp. 551–572roger pinkham
showed that if any law of first digits exists at all, and it does not change when every number is multiplied by the same constant, it has to be this one. change dollars to yen or metres to feet and a real dataset keeps its digits. that is why the law survives a change of units, and why invented numbers, which have no reason to be scale-free, fail it.
on the distribution of first significant digits. annals of mathematical statistics 32(4), 1961theodore hill
gave the proof that closed it. he showed that if numbers are drawn from a mixture of many different distributions, their first digits converge to the law even when none of the sources follow it on their own. that is the situation of any large pool of real transactions, which is what the counters on this site are.
a statistical derivation of the significant-digit law. statistical science 10(4), 1995, pp. 354–363newcomb found it, benford measured it, pinkham explained why it could not be otherwise, and hill proved it. the hook only counts.