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Base Rates

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

The base rate is how common something is before any specific evidence. Ignoring it makes rare things look common whenever tests can err.

Show

A rare condition plus a decent test still yields mostly false alarms — rarity outvotes accuracy.

Watch for

Base-rate neglect is the reasoning error with the highest real-world body count: medicine, security, hiring.