Data & ProbabilityProbability

The Monty Hall Trap

Switching doors doubles your chance of winning the car

One car, three doors. You pick door 1; the host opens door 3: a goat. Two doors left, so it's 50/50. Right?

You'll find out

  • Whether switching really matters
  • What the host knows that you don't
  • How even PhDs fell for the trap

Why it matters

Updating odds as new clues arrive is the skill behind many spam filters, and behind reading a medical test right.

About 3 min6 interactive slides · 5 questionsLesson 10 · Zone 2

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