Requirements   & Estimating   Scotch on the RocksEdinburgh, March 3-4 2011                            Peter Bell          ...
Agenda•   Requirements    •   Intent Driven Design    •   User stories 201•   Estimation    •   How much?    •   Estimatin...
Division of Labor •       My Job:     •    Present ideas •       Your Job:     •    Discriminate, select, adapt, experiment
About you•   Consultant/in-house/product    development?•   Team size?•   Number of projects/year?•   Agile?•   User stori...
Requirements
Before user stories . . .        What should we build?
Intent Driven Design •   Business intent •   Audiences •   Objectives •   User stories (tasks)
User stories (1) •   INVEST     •   Independent     •   Negotiable     •   Valuable     •   Estimable     •   Small     • ...
User stories (2) •   Tracer bullets, not tasks •   Splitting stories by ...     •   Data     •   Validation     •   Paths ...
Estimation
Why estimate?
Why estimate?•   Good reasons to estimate:    •   Go/no go based on cost    •   Market window    •   ROI comparison
Why estimate?•   Good reasons to estimate:    •   Go/no go based on cost    •   Market window    •   ROI comparison•   Bad...
Why estimate?•   Good reasons to estimate:    •   Go/no go based on cost    •   Market window    •   ROI comparison•   Bad...
Estimating scope•   Ideal days (load factor)•   Story points    •   1,2,3,5,8    •   0?    •   10,20,30,51?•   T-shirt siz...
Estimating scope•   Planning poker•   Keys:    •   Delphi technique    •   Independent estimates    •   1-3 hours, 1-3 ses...
Estimating scope•   Magic/Affinity Estimating    •   Large number of stories    •   Experienced team
Estimating time•   Estimating velocity    •   Historic rate    •   Run iterations    •   Make forecasts•   Burn down charts
Managing risk
Four types of feature •   Rocket science •   Lab experiment •   New to you •   with a twist
Dealing with dark matter • What you don’t know does hurt you ...   • But obviously . . .   • The dreaded API and technical...
Making commitments
Fixed duration •   Optional features •   Team size •   Real options •   Schedule buffer
Fixed price •   Optional features •   Price buffer •   Scheduling flexibility?
Breaking the iron triangle
Breaking the iron triangle  Requirements are never fixed!
Q&A                                 Twitter: peterbell•       Requirements                Email: peter@pbell.com    •    I...
Upcoming SlideShare
Loading in …5
×

Requirements and estimating

1,517 views
1,366 views

Published on

Estimating and requirements gathering are an important part of all our jobs. Your boss or your client doesn't care about FW/1, CF-ORM or Code Generation, but improving your requirements gathering and estimating skills can make a big difference in how they value your skills.

Learn best practices for more accurately specifying and estimating projects using a range of proven patterns developed from specifying and estimating over 400 web applications over more than ten years.

Published in: Technology, Business
0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
1,517
On SlideShare
0
From Embeds
0
Number of Embeds
14
Actions
Shares
0
Downloads
25
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide

Requirements and estimating

  1. 1. Requirements & Estimating Scotch on the RocksEdinburgh, March 3-4 2011 Peter Bell Railo
  2. 2. Agenda• Requirements • Intent Driven Design • User stories 201• Estimation • How much? • Estimating scope • Managing commitments • Estimating duration • Fixed duration• Managing risk • Fixed price • Four types of features • Breaking the iron triangle • Dealing with dark matter
  3. 3. Division of Labor • My Job: • Present ideas • Your Job: • Discriminate, select, adapt, experiment
  4. 4. About you• Consultant/in-house/product development?• Team size?• Number of projects/year?• Agile?• User stories?• Estimates required?• Fixed bid required?
  5. 5. Requirements
  6. 6. Before user stories . . . What should we build?
  7. 7. Intent Driven Design • Business intent • Audiences • Objectives • User stories (tasks)
  8. 8. User stories (1) • INVEST • Independent • Negotiable • Valuable • Estimable • Small • Testable
  9. 9. User stories (2) • Tracer bullets, not tasks • Splitting stories by ... • Data • Validation • Paths • Edge cases • Isolate cross cutting concerns • Make it work, then pretty/fast
  10. 10. Estimation
  11. 11. Why estimate?
  12. 12. Why estimate?• Good reasons to estimate: • Go/no go based on cost • Market window • ROI comparison
  13. 13. Why estimate?• Good reasons to estimate: • Go/no go based on cost • Market window • ROI comparison• Bad reasons to estimate • Because . . .
  14. 14. Why estimate?• Good reasons to estimate: • Go/no go based on cost • Market window • ROI comparison• Bad reasons to estimate • Because . . .• Ask whether: • Time, price or both? • Will estimate matter? • Accuracy required?
  15. 15. Estimating scope• Ideal days (load factor)• Story points • 1,2,3,5,8 • 0? • 10,20,30,51?• T-shirt sizes• Story count
  16. 16. Estimating scope• Planning poker• Keys: • Delphi technique • Independent estimates • 1-3 hours, 1-3 sessions • 2-6 people
  17. 17. Estimating scope• Magic/Affinity Estimating • Large number of stories • Experienced team
  18. 18. Estimating time• Estimating velocity • Historic rate • Run iterations • Make forecasts• Burn down charts
  19. 19. Managing risk
  20. 20. Four types of feature • Rocket science • Lab experiment • New to you • with a twist
  21. 21. Dealing with dark matter • What you don’t know does hurt you ... • But obviously . . . • The dreaded API and technical risk • Well, that’s almost right . . . • Now that I see it . . . • Mitigate: • Set expectations • Technical spikes • Track and refine
  22. 22. Making commitments
  23. 23. Fixed duration • Optional features • Team size • Real options • Schedule buffer
  24. 24. Fixed price • Optional features • Price buffer • Scheduling flexibility?
  25. 25. Breaking the iron triangle
  26. 26. Breaking the iron triangle Requirements are never fixed!
  27. 27. Q&A Twitter: peterbell• Requirements Email: peter@pbell.com • Intent Driven Design • User stories 201• Estimation • How much? • Estimating scope • Managing commitments • Estimating duration • Fixed duration• Managing risk • Fixed price • Four types of features • Breaking the iron triangle • Dealing with dark matter

×