What determines the activity estimate range?

The activity estimate range is determined by the difference between the optimistic estimate and the pessimistic estimate. In project management, the optimistic estimate represents the best-case scenario for how long an activity could take, while the pessimistic estimate reflects the worst-case scenario.

By subtracting the optimistic estimate from the pessimistic estimate, you obtain the activity estimate range, which illustrates how much uncertainty there is in the estimated duration. This range helps project managers assess the risk associated with completing the project on time and aids in resource allocation and scheduling.

Understanding this range is critical for developing accurate project timelines and ensuring that the project stays on track. It helps identify potential variances and prepares the team to manage uncertainties that may arise during the project lifecycle. Therefore, the calculation of (P - O) accurately captures this range and is an essential concept in effective project management practices.