multiple choice

The returning-planes problem

Statistics & Inference · Bias · easy · Company-context scenario · 5 min

In WWII, analysts studied bullet holes on planes that RETURNED from missions and proposed armoring the most-hit areas. Abraham Wald disagreed. What was his insight?

Evaluation criteria

Picks the option the reasoning in the prompt supports

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Source

Company-context scenario built from real product constraints. It is not represented as a verbatim interview question.

Your answer

A. Armor the most-hit areas, since that's where planes take damageB. Armor the LEAST-hit areas on returning planes — hits there likely downed the planes that never came back (survivorship bias)C. Add armor everywhere equallyD. The data was random, so ignore it

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The returning-planes problem

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Your answer

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