Software estimation strategy and technique

1. Software Estimation 🧩
1 March 2024
Panji Gautama

2. Software Estimation 🧩
1. When does
Estimation
happen
1 1. Software
Estimation
Technique
2

3. When does Estimation happen
Why do we need Estimation ?
💰
Decision Making
󰤫
Coordination
🌋
Risk Management

4. When does Estimation happen
Common Estimation Pitfalls
📝
Misaligned
Estimation
Checklist
🫨
Uncertainties
Not
Included
🎯
Estimates
considered
Deadline

5. When does Estimation happen
Stages of Development

6. When does Estimation happen
Software Estimation Is Hard. Do It Anyway.
⚖
Hofstadter’s
Law
🔢
Arbitrary
Scoring Systems
🏹
Estimates
is
Skill

7. Software Estimation 🧩
1. When does
Estimation
happen?
1 1. Software
Estimation
Technique
2

8. Software Estimation Technique
Story Points

9. Software Estimation Technique
T-Shirt Size

10. Software Estimation Technique
Top-Bottom x Bottom-Up

11. Software Estimation Technique
Estimation as a Skill
1⃣ Break down work into less-complex tasks
2⃣ Estimate uncertainty
3⃣ Do the math to get expected- and worst-case estimates
4⃣ Refine, if needed
5⃣ Track your accuracy, so you can improve over time

12. Software Estimation Technique
Estimation as a Skill
1⃣ Break down work into less-complex tasks
2⃣ Estimate uncertainty
3⃣ Do the math to get expected- and worst-case estimates
4⃣ Refine, if needed
5⃣ Track your accuracy, so you can improve over time

13. Software Estimation Technique
1⃣ Break down work into less-complex tasks
● Map complexity to actual time units.
● Use real wall-clock hours and days
○ Don’t assume engineers will write code 8 hours a day.
● Try to capture realistic expected times
○ Don’t be overly optimistic
○ Don’t be overly pessimistic
Complexity Time
small 1 day
medium 3 days
large 1 week (5 days)
extra-large 2 weeks (10 days)

14. Software Estimation Technique
2⃣ Estimate uncertainty
● Measure uncertainty level
● Identify action items to reduce the uncertainty

15. Software Estimation Technique
3⃣ Do the math
Task Complexity Uncertainty Expected Worst-case
User Story A small low 1 day 1.1 days
User Story B large moderate 5 days 7.5 days
Refactor XYZ medium extreme 5 days 25 days
RFC medium medium 3 days 4.5 days
Deploy small low 1 days 1.1 days
Total: 15 days 39 days

16. Software Estimation Technique
4⃣ Refine, if needed
● Timeboxing
● Research
● Spike or PoC
● JFDI

17. Software Estimation Technique
5⃣ Track your accuracy, so you can improve over time
Task Complexity Uncertainty Expected Worst-case Actual
User Story A small low 1 day 1.1 days 0.5 Days
User Story B large moderate 5 days 7.5 days 8 Days
Refactor XYZ medium extreme 5 days 25 days 20 Days
RFC medium medium 3 days 4.5 days 5 Days
Deploy small low 1 days 1.1 days 0.5 Days
Total: 15 days 39 days 34 Days

18. thank you
linkedin.com/in/panjigautama