Mathematics
The t-Distribution and Small-Sample Confidence Intervals
Quick fact
The t-distribution was published in 1908 by William Sealy Gosset under the pseudonym 'Student' because his employer, Guinness Brewery, wouldn't allow employees to publish research.
Why this is interesting
Think you can use the normal curve for any sample? When your sample is small, that curve may be quietly leading you astray. What's the hidden adjustment that keeps your results honest?