This is a Lexicon entry: the mechanism, when it shows up, and the countermeasure. The full correction, with real-world cases and the audit prompt, hasn't been written yet.
Definition
The tendency to make predictions by focusing on the specific details of a situation (inside view) rather than asking "what usually happens in cases like this?" (outside view / base rate thinking). The outside view is almost always more accurate but the inside view feels more real.
When it shows up
Estimating how long your project will take, how likely your marriage will last, how your startup will perform. Any forecast about a specific situation where you have rich internal details.
Failure mode
The specific details of your own case feel so concrete that they crowd out the base rate for the class of case. You forecast from the inside, treating your situation as uniquely positioned and ignore that most situations in this class feel uniquely positioned too.
Countermeasure
Before using your own plan as the forecast, look up what actually happened to the last twenty projects/marriages/startups that looked similar. Use their outcome distribution as your anchor, not your plan.
Related traps
Also connected in the map5 more, locked
Credit & first seen
DiscoveredDeveloped by Kahneman and Lovallo (1993); central to Philip Tetlock's superforecasting research. source ↗
Also revealed
Entry #29 of 631 in The Lexicon · see the full Lexicon