Estimating in Points
Explore Agile estimation methods by understanding the use of points as a relative measure for work item sizes. Learn why point estimation is faster, more precise, and less threatening than hours, and how to involve teams in creating realistic estimates. Discover best practices for selecting estimation units and updating estimates to improve project velocity and planning accuracy.
Overview
Estimates in hours are an absolute measure, while a relative measure is often wiser, easier, and less threatening. Let’s explore this in greater depth. The picture below shows the skyline of Chicago.
Suppose that every building in this skyline is a work item. Just like work items, buildings vary greatly in terms of size. Suppose we want to make an estimate of the total size of the work items in a project in hours. This corresponds to estimating the total height in meters of the buildings in the skyline. Now we have to estimate the height of each individual building. The chance that this estimate is quite wrong is enormous. Try it.
Are higher points usually assigned to a lower complexity story?
Suppose we were to make the estimate on the basis of a fictitious scale that’s representative of the height of the buildings. For instance, a scale of one to five. Now, the buildings can be compared to each other when estimating. It’s relative. As a guideline, we give the tallest building the value five. Without too much trouble, the other buildings in the picture can be placed on the same scale, relative to the tallest building. This approach results in an estimate within minutes, say 200 points. Work items in a project can be expressed using a similar ...