Random data always looks like it has patterns — your brain finds them anyway

The clustering illusion is the tendency to see meaningful clusters in what's actually random noise, like wartime Londoners convinced German V-1 rockets were targeting specific neighbourhoods, when statisticians later showed the strike pattern matched pure chance. The related 'Texas sharpshooter fallacy' describes cherry-picking a cluster after the fact and calling it proof.

— Thomas Gilovich, How We Know What Isn't So — Free Press, 1991
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