CST Agile Estimation Techniques & User Stories 2 — Questions and Answers
Question 1: What best describes 'relative estimation' in the context of Agile?
- Estimating items based on calendar time relative to the current date
- Comparing items to each other to determine relative effort, complexity, or size (Correct answer)
- Using historical data from similar past projects to size current work
- Estimating effort relative to the team's highest-skilled member's capability
Correct answer: Comparing items to each other to determine relative effort, complexity, or size
Relative estimation compares items against each other (e.g., 'this story is about twice as complex as that one') rather than assigning absolute time values, which tends to produce more consistent results.
Question 2: What is a 'spike' in Agile, and what is its primary purpose?
- A very high-priority User Story that must be completed before any other work in a Sprint
- A time-boxed research or exploration task designed to reduce uncertainty before estimation (Correct answer)
- An estimation unit equivalent to one story point used in smaller teams
- A technique for rapidly prototyping new user-facing features
Correct answer: A time-boxed research or exploration task designed to reduce uncertainty before estimation
A spike is a time-boxed effort to investigate a technical question or reduce uncertainty, allowing the team to make more informed estimates or design decisions on subsequent stories.
Question 3: What does a 'Definition of Ready' (DoR) ensure about User Stories before Sprint Planning?
- That all User Stories have been fully designed and documented before development begins
- That User Stories meet agreed lightweight criteria making them clear and small enough to plan (Correct answer)
- That the Product Owner has signed off on all stories before they can be worked on
- That automated acceptance tests have been written before development begins
Correct answer: That User Stories meet agreed lightweight criteria making them clear and small enough to plan
The Definition of Ready ensures stories have met lightweight criteria — such as being small enough and having clear acceptance criteria — so the team can confidently plan and execute them in a Sprint.
Question 4: T-shirt sizing (XS, S, M, L, XL) is best used for which estimation scenario?
- Technical architecture decisions that require precise effort estimates during Sprint Planning
- Initial high-level estimation of many backlog items, especially when details are still uncertain (Correct answer)
- Tracking team velocity across multiple Sprints for stakeholder reporting
- Assigning specific work items to individual team members based on skill level
Correct answer: Initial high-level estimation of many backlog items, especially when details are still uncertain
T-shirt sizing is a quick, relative estimation technique ideal for early-stage backlog grooming when items lack sufficient detail for precise story point estimates.
Question 5: According to the INVEST criteria, what does 'Negotiable' mean for a User Story?
- The business value of the story can be changed by the development team if needed
- The story's scope and details can be discussed and adapted through team collaboration (Correct answer)
- The story's acceptance criteria are open to reinterpretation by developers during the Sprint
- The story can be moved between Sprints without notifying the Product Owner
Correct answer: The story's scope and details can be discussed and adapted through team collaboration
Negotiable means a User Story is not a rigid contract; its scope and implementation details are open for collaborative discussion between the team and the Product Owner.
Question 6: Why should the Developers, not the Product Owner, be responsible for estimating User Stories?
- The Scrum Guide explicitly and exclusively assigns estimation authority to Developers
- Product Owners are not permitted to attend Sprint Planning under the Scrum framework
- The Developers do the actual work and therefore have the most accurate understanding of effort (Correct answer)
- Estimation is a core Scrum Master competency required for CST certification
Correct answer: The Developers do the actual work and therefore have the most accurate understanding of effort
Since Developers perform the actual work, they have the deepest understanding of technical complexity, risk, and effort involved, making their estimates most accurate and credible.
Question 7: What is 'affinity estimation' and when is it most effectively used?
- Estimating based on team members' affinity for certain technologies or frameworks
- A fast, silent group technique for sizing many backlog items by grouping similarly-sized items (Correct answer)
- An estimation method that requires unanimous team agreement before assigning points
- A technique borrowed from SAFe for Program Increment-level capacity planning
Correct answer: A fast, silent group technique for sizing many backlog items by grouping similarly-sized items
Affinity estimation is a rapid, silent technique where team members group items by relative size, making it especially efficient for quickly sizing large backlogs without lengthy discussion per item.
CST Agile Estimation Techniques & User Stories 2
What best describes 'relative estimation' in the context of Agile?