What is a What-If Scenario Analysis & Simulation?
What-if scenario analysis tests the plan against specific hypotheticals — what if the permit slips 60 days? what if the main supplier fails? — recalculating the schedule and cost for each scenario to see consequences and prepare responses. Simulation generalizes it: instead of a handful of hand-picked scenarios, techniques like Monte Carlo run thousands of randomized ones and return probability distributions.
The family tree the exam expects: sensitivity analysis finds which variables matter; what-if examines chosen scenarios; Monte Carlo simulates all of them at once, statistically.
Worked example
Before committing to a plant-shutdown window, the planner runs three what-ifs: crane arrives late (+4 days), weld inspections fail at double rate (+6 days), both together (+9 days — worse than the sum, because crews demobilize). The owner books a 10-day contingency window instead of 5. The Monte Carlo run afterward confirms it: 92% of simulated outcomes fit inside the new window.