The Paradox Portal
Mathematical

Survivorship Bias

We overestimate success by focusing on survivors

Overview

A logical error where we concentrate on things that survived a selection process while overlooking those that didn't.

WWII: researchers studied returning planes' bullet holes to add armor. Abraham Wald noted the pattern showed where planes could be hit and survive. Armor should go where holes weren't - because planes hit there didn't return. We see survivors, not the dead.

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