Psychologycalendar_todayLast updated: Apr 2026
What is Base Rate Fallacy?
/beɪs reɪt ˈfɔːləsi/
A cognitive error where you ignore general statistics about how common something is and focus instead on specific details, leading you to misjudge the real odds. You focus on the vivid story and forget the baseline number.
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Everyday Example
You see one news story about a plane crash and become terrified of flying, ignoring the fact that driving to the airport is statistically 100 times more dangerous.
publicReal-World Application
“Doctors sometimes fall victim to this when they see unusual symptoms in a patient and diagnose a rare disease instead of correctly identifying the common condition that matches those symptoms.”
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Did you know?
Psychologists Daniel Kahneman and Amos Tversky documented this bias in the 1970s with their famous 'Linda Problem' experiment, which revolutionised how we understand human decision-making.
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Key Insight
The most vivid or memorable information is rarely the most statistically likely—always check what actually happens most of the time.
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