Two-time method
The two-time method is a rudimentary estimation method in project management .
Estimating the time and effort for a work package in a project is often problematic:
- Since there is usually insufficient knowledge of the content of the work package, the estimate is inevitably subject to uncertainty
- This uncertainty is greater, the greater the development and research part of the package (see Cone of Uncertainty )
- Nevertheless, this estimate is then often viewed as a fixed " deadline "
- Project staff are usually reluctant to give an estimate of the time and effort, because they are not yet clear about the exact scope and neither can they be
- When it comes to new types of tasks, people tend to be too optimistic about the effort required
These problems can be alleviated by the two-time method by estimating a best and a worst case for a work package. The “true” estimate will most likely be within the estimated uncertainty. Since the uncertainty becomes smaller in the course of the project (see Cone of Uncertainty ), the estimates must be revised by the project manager at regular intervals. Since most PM tools cannot process uncertainties, the mean value can be used for planning
be used. This very simple procedure is refined in the three-time method with an additional weighting.
See also: