Agile Scrum Estimation
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The document discusses different approaches to estimation in waterfall and Scrum methodologies. In Scrum, teams estimate their own work in story points, which are relative units based on size and complexity. Story points help drive cross-functional behavior and do not decay over time. Ideal days estimates involve determining how long a task would take with ideal conditions and no interruptions. Planning poker uses story point cards to facilitate discussion and reach consensus on estimates. Release planning in Scrum involves estimating velocity over sprints to determine how many product backlog items can be completed.
Agile Scrum Estimation
- 1. Estimation - ThoughtsScrum MasterPrasad Prabhakaran
- 2. AgendaEstimation : waterfall Vs Scrum
- 3. Product back log estimation unitsStory points Ideal timeTechniques for estimation
- 6. Summary
- 7. References Water fall Vs Scrum estimationManager estimatesTask is assigned Time based estimates Work break down estimates Team estimates their own workSelf organized Size based - unit less relative estimatesFeature break down estimates Water fall Scrum
- 8. Estimating user stories We are talking about product backlog estimatesTwo techniques Story points
- 9. Ideal days Estimate size & derive duration
- 10. Story pointsThe bigness of the task
- 11. Influenced by how hard it is ? & How much there is?
- 12. Relative values are what is important , for eg: login screen is a 2,search feature is 6
- 13. Points are unit less
- 14. On order of magnitude
- 15. Clue is determine complexity factor ( for eg: due to requirement and technology)
- 16. What is your t-shirt size ? Estimating in ideal time How long it would take if a) It is all you worked on b) You had no interruption c) Every thing you need is available for eg: Ideal time for a football game is 60 minutes, but elapsed time is much longer
- 17. It is easier to estimate in ideal time than in ‘actual ‘/ ‘elapsed’ time, because need to consider all the factors that affect elapsed time at the same time you are estimating.What is your office timings? What is your focus factor?
- 18. Ideal time Vs Story point approaches Story points help drive cross-functional behavior• Story point estimates do not decay• Story points are a pure measure of size• Estimating in story points is typically faster• My ideal days cannot be added to your ideal days• Ideal days are easier to explain outside the team• Ideal days are easier to estimate at first
- 19. Three levels of planningRelease plan -> Product back logSprint / iteration plan -> Sprint back logDaily plan -> Daily Scrum / stand up meeting
- 20. Best practice Prefer story points...but they make some teams uncomfortable, so start with ideal time• Gives the team a nice foundation for the initial stories, helps team get started• Define “1 story point = 1 ideal day” Then gradually convert team to thinking in unit-less story points “This story is like that story.”• Stop talking about how long it will take
- 21. Estimation techniqueEstimate by Analogy Comparing a user stories to other – Relative sizing Planning poker game Each estimator is given a deck of cards, each card has a validestimate written on it• Customer/Product owner reads a story and it’s discussedbriefly• Each estimator selects a card that’s his or her estimate• Cards are turned over so all can see them• Discuss differences (especially outliers)• Re-estimate until estimates converge
- 22. Why Planning poker worksEmphasizes relative estimating• Focuses most estimates within an approximate one order of magnitude• Everyone’s opinion is heard• Estimators are required to justify estimates• It’s quick• It’s funwww.planningpoker.com
- 23. Sprint planning What is the sprint duration? 3 weeks/ 4 weeks etc..
- 24. Availability of team members
- 25. What is the ‘focus factor’ ( from history, Available days ÷ Story points completed
- 26. Velocity - use historical, very difficult in initial sprints, forecast it. best in range, total number of story points can be completed in a sprint
- 27. Pick up product backlogs based on your velocity Release planning – fixed time Determine how many sprints you have ( (desired date – today’s date)/ sprint duration ) 2. Estimate velocity as a range3. Multiply low velocity X number of sprints• Count off that many points• These are “Will Have” items4. Multiply high velocity X number of sprints• Count off that many more points• These are “Might Have items”
- 28. Summary & Key takeaway Objectives Estimate - Product Backlog items / story points
- 29. Many Tasks leading up to the objectives
- 30. Relative value should be used for estimating - story points
- 31. Absolute value for tasks
- 32. Estimate product back log items during release / product planning
- 33. Estimate tasks during sprint planning meetings
- 34. Velocity - average story points completed in sprints Referenceshttp://infoq.com/minibooks/ scrum-xpfrom- the-trencheswww.sprint-it.de/scrum-checklistsConfessions of a serial product owner Based on a true story Anna ForssJoin Agile Alliance group @ LinkedinJoin Agile alliance charter CoP @ Oskar.satyam.com Go to oskar.satyam.com ( give u r network id and password) Select CoP-> join CoPCoP Sites -> Agile Alliance
- 35. Q &A Thanks