Mental model · Numbers & chance
Base rates
Base rates: How common something is in general, before you consider the specific case in front of you.
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How common something is in general, before you consider the specific case in front of you.
Try it now
Take a judgement you are making about a specific person, project or opportunity. Ask how often things in that category turn out that way.
What to do with the answer
Start your estimate at the base rate, then adjust for the specifics — and adjust less than you want to.
Where it misleads
A badly chosen reference class gives a confidently wrong number. Always say which class you used.
The module it belongs to
- Logical Thinking — Reason consistently
The book behind it
- Thinking fast and slow — Its big ideas, in our own words.