How much time would you budget?
Forecasting only the imagined plan can miss variation from similar past projects.
Inside this model
A seeded teaching sample adds delay of 0–12 days to the best-case estimate across 100 hypothetical projects. The buffer adds estimate×buffer/100; the plot compares budgeted time and the sampled completion distribution.
Out in the world
A practical use
Use outcomes of previous similar tasks to set a schedule, then compare your planned buffer.
A useful lens. Not a universal law.
- Uniform delay is illustrative, not a calibrated reference class for your project.
Associated thinkers
Further reading
Explore the original research or the teaching reference behind this experiment.
Buehler, Griffin and Ross — Exploring the Planning Fallacy ↗