The mathematics of uncertainty
Entropy measures uncertainty: how surprised you expect to be by a random outcome. A fair coin is maximally uncertain; a two-headed coin holds no surprise at all. Claude Shannon turned this into a number, the expected surprise, where a rare event's surprise is −log p(x) (rarer means more surprising).
🔒 This is a Pro lesson — the interactive figure, worked examples, quiz and practice open with Pro access.
▶ Entropy