5.1 How Much Does That Ox Weigh?

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5.1
How Much Does That Ox Weigh?

Picture a country fair in 1907: stalls, the smell of hay, people chatting — and at the centre, proudly displayed, a massive ox. About 800 people line up to take part in a contest: guess the animal’s weight.

Among them is Francis Galton — yes, the same one — who carefully collects all the entries. And that’s when he notices something astonishing: no one guesses the exact weight (1,198 pounds), yet the average of all guesses is 1,200 pounds — only two pounds off.

As if the crowd, as a whole, showed a level of accuracy almost none of its members had individually.

Galton is impressed — and, in a way, unsettled.

He, the father of eugenics and believer in selecting the “best,” is forced to admit — reluctantly — that “this result gives more weight to the reliability of a democratic judgment than one might have expected.”

He writes about it in Nature, in an article significantly titled Vox Populi.

More than a century later, we try something similar. There isn’t an ox in front of you… but there is a container full of candies. So — how many?