Estimating Size with Story Points
Estimating in Ideal Days
Techniques for Estimating
Choosing between Story Points and Ideal
Story Points Are Relative
› Story points are a unit of measure for expressing
the overall size of a user story, feature, or other
piece of work.
› Get Started with smallest or medium user story.
› Is a measure of a team’s rate of progress.
› Velocity Corrects Estimation Errors.
Ideal time vs. Duration.
Ideal Time and Software Development.
› The story being estimated is the only thing you’ll work on.
› Everything you need will be on hand when you start.
› There will be no interruptions.
Ideal Days as a Measure of Size.
One Estimate, Not Many.
Estimates Are Shared
› estimates are best derived collaboratively by the
team, which includes those who will do the work.
There are two reasons for this.
The Estimation Scale
› “1, 2, 3, 5, and 8” or “1, 2, 4, and 8”.
› Could include “0”.
Deriving an Estimate
› Expert opinion
› Smaller Sessions
› When to Play Planning Poker
Considerations Favoring Story Points
› Story points help drive cross-functional
› Story-point estimates do not decay.
› Story points are a pure measure of size.
› Estimating in story points typically is faster.
› My ideal days are not your ideal days.
Considerations Favoring Ideal Days
› Ideal days are easier to explain outside the
› Ideal days are easier to estimate at first.
Agile Estimating and Planning by Mike