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William Sealy Gosset worked at Guinness as a chemist and brewer and developed methods of statistical inference for small samples. He published under the pseudonym "Student". His employment as a chemist is independently recorded by MacTutor; the Dictionary of Irish Biography identifies him as an applied statistician and brewer and explains the pseudonym policy. ^{[ref] [ref]}

The 1908 paper The Probable Error of a Mean appeared in Biometrika 6(1), pages 1–25, with the byline "Student". Its introduction identifies the uncertainty introduced by estimating a standard deviation from few observations and explicitly assumes a normal distribution. Sections II and III develop the relation between sample spread and the standardized sample mean. Its notation uses a sample spread with divisor $n$ and calls the ratio $z$; with that convention, the modern $T$ equals $\sqrt{n-1}z$. The modern exact independence argument is given under studentized normal sample mean. ^[ref]

Section VI describes a physical sampling check: 3,000 cards carrying existing paired measurements were shuffled, then divided into 750 groups of four. He compared observed frequencies of sample spread and standardized sample mean with theoretical frequencies. This was a check using finite, grouped, approximately normal distribution data; it did not prove exact calibration for arbitrary populations. ^[ref]