Introduction to three-point estimation technique for software development, and learning to apply it in 10 steps with an example project. Lightning talk given at Warsaw Ruby User Group in June 2019. ( https://www.youtube.com/watch?v=csVCEsf-1uQ ) For better quality, please download the presentation

1. Three-point estimation
Sakir Temel

2. - CTO of Visuality ~3 years
- Over 130+ project estimations which are from different domains, sizes, countries, clients.
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3. Objectives
- Know how to apply Three-point estimation
technique in 10 steps with an example
project
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Out of scope
- Statistical perspective to 3 point
estimations, why the formula matters
- Purpose of estimations
- Team work on estimations
- Complex project estimations
- Different estimation techniques
- Importance of estimations
- Importance of realistic estimations
- Work breakdown structure

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An application to show all
followed ruby user groups’
Youtube channels statistics to
evaluate the performance,
and also see the effects of
improvements done lately
with metrics
Project: RUGS

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How much will it cost?
(it all started here)
(Hmmm.. channel crud, api.
channel crud is 0.5 day with
tests and everything, api will
be 0.5 day)
it can be done in a day, it’s
pretty easy!
(yay, I’m positive!, the person
who asked for estimation will
be happy to hear that!(and
also will not judge me, and
ask questions))
Project: RUGS

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How much will it cost?
(it all started here)
Professional approach
- Your mockup is pretty
helpful. Would you
provide the user
stories or would you
like us to help to you?
-> (generate user
stories by us)
Project: RUGS

9. 9
- As a guest I can
access to the
application
- As a guest I can add
a youtube channel
link to track and see
in the list
- As a guest I can see
the stats of each
channel from youtube
data
Project: RUGS

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22. Let’s give our estimations
Our numbers taken from excel are 20.67+-3.65 hours
- Techniques are there to help making decisions, not to make the decisions
- Let’s interpret that for the decision maker/reviewer. Not only numbers, but
value as you can, easily.
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23. Compare the estimates
We will do it in 1 day, everything will be great.
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The project cost estimate range is 20+-4 hours
Estimation is based on the mockup given and
stories, the technologies going to be used
Heroku, Rails
After the first story the production access will be
given to watch the development
Our estimation is done by using 3 point
estimation for enhanced accuracy

24. Links worth checking
- https://en.wikipedia.org/wiki/Three-point_estimation
- https://en.wikipedia.org/wiki/Work_breakdown_structure
- https://www.youtube.com/watch?v=Am9tlsmcnPI
- https://www.slideshare.net/tuomasniinimaki/3-estimation
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25. Thank You!
Sakir Temel

26. Q&A & Key takeaways
- There are techniques, everyone should learn. Study more.
- Make estimation and its process transparent and welcoming everyone
- Estimations are affecting more things than you can imagine. Planning, performance, motivation,
strategy, resource planning, sales, knowledge sharing, etc.
- It’s just the beginning. Learn more, question more, teach more
- But don’t forget, Techniques are there to help making decisions, not to make the decisions
- Good techniques create awareness of the project’s details(size, risks, approaches, assumptions)
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