Agile estimating and planning in a Scrum project will not prevent your boss from asking: “Will you make the date?” This video explains how to use Scrum and the “Cone of Uncertainty” to provide an answer like: “60% probability.”
The Cone of Uncertainty is a project management term that was developed by Barry Boehm. It describes the level of uncertainty existing at different stages of a project. In short, we become more certain of our estimates as we learn more about what we’re estimating. Research show that at the beginning of the project, estimates have in general an uncertainty of factor 4 on both the high side and the low side. This means that the actual effort or scope can be 4 times or 1/4th of the first estimates.