1. Define a scale (ballpark approximation)—Scale can be as wide as the expected project length or it can be some portion of it. It is not to be confused with an overall estimate of the project. It might be roughly similar in length, but the actual project estimate is produced later.
2. Define a resolution—Resolution represents the number of chunks in which we need to break up work in order to gain a sufficient statistical grip. Higher resolution provides an increased certainty, but it also costs progressively more to sustain.
3. Initial estimation and sizing—Based on the desired resolution and other factors, we need to design ranges for estimating effort. Once we go through the initial estimation, we can size the project and take a first guess at whether the team has enough capacity.
4. Adjust for calendar time—It is crucial to convert the effort estimates into calendar time. This is because the actual completion data we collect in the next step is based on calendar time. Once we convert effort estimation into calendar times, we can also speculate about optimistic and pessimistic completion dates for the project.
5. Collect data—Estimation data is only one input for the forecast. Tracking the actual implementation times and observing other contextual factors provide another set of input information. The relationship between estimates and actual completion times becomes the basis for adjustments and predictive accuracy.
6. Identify trends and scenarios—Once we have collected enough data, we can start analyzing, making projections, and evaluating different scenarios.
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