Frameworks · Build · 58

The outside view

Use the average of three past tasks, not your feeling.

SWe reviewed the research on it.Starting

How to use it

Before committing to a deadline, find three similar past tasks and how long they really took. Use their average, not your feeling. With no history, take your best guess and add half.

How sure we are

S Evidence: strong. Large trials or many studies, pointing the same way.

Sources

the planning fallacy (Buehler, Griffin & Ross 1994, and many since).

Not medical, legal or financial advice.

Put it to work

One framework a day, inside a system.

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