On March 7, 1907 — almost 111 years ago to the day — the English statistician Francis Galton published a peculiar observation.
At a county fair held in Plymouth, 800 visitors had participated in a competition to guess the weight of an ox. While most people's estimates were too high or too low — falling an average of 37 lbs. away from the true weight of 1,198 lbs. — the median of everyone's guess was off by only 9 lbs., or less than 1 percent of the true weight of the ox.