Estimation Criteria
Agreed rules or benchmarks the team uses to size work items so relative sizes stay consistent and the need to re-estimate is reduced. These criteria can take different forms, most commonly story points or ideal time.
Key Points
- Keep relative sizing stable across backlog items to support predictable planning.
- Reduce re-estimation by aligning new work to known reference stories.
- Can be expressed as story points or ideal time, depending on team preference.
- Work best when defined and maintained by the whole team and revisited periodically.
Example
A Scrum team agrees on estimation criteria: a 1-point story is very small, low risk, and can be finished within part of a day; a 3-point story has moderate complexity; an 8-point story involves higher uncertainty or several integration steps. Using these criteria, they quickly estimate new backlog items with planning poker, keeping relative sizes consistent without frequent re-estimation.
PMP Example Question
A team keeps revisiting and changing their backlog estimates, causing planning churn. What should the project manager implement to maintain consistent relative sizes and minimize re-estimation?
- Create a more detailed WBS dictionary
- Establish clear estimation criteria (e.g., story points or ideal time)
- Hold longer daily standups
- Increase the frequency of retrospectives
Correct Answer: B — Establish clear estimation criteria
Explanation: Estimation criteria provide shared benchmarks (such as story points or ideal time) that keep relative sizing consistent and reduce the need to re-estimate.
HKSM