USP Estimation - SwanseaCon 2016
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USER STORY POINT ESTIMATION
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Transcript of USP Estimation - SwanseaCon 2016
USER STORY POINT ESTIMATION
Hello!I am Fred Heath
Developer, Problem solver, Ruby / Nim evangelist, Agile practitioner.
You can find me at:
FredAtBootstrap
www.bootstrap.me.uk
SCRUM ESTIMATION
● Planning Poker
● T-Shirt Size
● Fruit Eating
● …and others
Story Points
“There is currently no standard unit of
measurement in software development
What’s this all about
● Current estimation methods not fit for purpose● A new algorithmic-based, empirical way introduced:
USP estimation
USP = User Story Point
4 - easy
4 - easyNot to
me - 16
#!@%
but, look here………………..easy, see?
I suppose you’re right,4 then!
Ben implements the story
Ben struggles
Jerry helps
Ben struggles some more
PO getting stressed
Scrum begins...
What went wrong
Environmental factors ignored
Ben unfamiliar with project, programming language and application domain.
Technical factors ignored
Asynchronous processing is inherently complex, setup is not trivial.
Human interaction factors ignored
Jerry charismatic and influential leader. Peer pressure always wins.
Key problems with current estimation methods
● Inconsistent
● Subjective
● Unreliable
Velocity Assumptions
● Stable previous velocity
● Team doesn’t change
● Sprint duration doesn’t change
● Technology / platform doesn’t change
● Individual productivity doesn’t change
USER STORY POINT ESTIMATION
An empirical, algorithmic-based estimation method
Use Case Point Estimation
for Object-Oriented, Use-Case based development
Use Case Points
Environmental Factors (EF)
Project familiarity, application experience, motivation, language complexity, etc.
Technical Factors (TF)
Complex algorithms, concurrency, cross-platform support, etc.
Use Case complexity (UUCP)
Simple, average or complex
Use Case Points = UUCP * TCF * ECF
UCP References1. Karner, G, 1993, “Metrics for Objectory”. Diploma thesis, University of
Linköping, Sweden. No. LiTHIDA-Ex-9344:21. December 1993.2. Smith, John, 1999, “The Estimation of Effort Based on Use-Cases.
Rational Software.Cupertino, CA.TP-171. October 1999.3. Anda, Bente, D. Dreiem, Dag Sjøberg and Magne Jørgensen, 2001,
“Estimating Software Development Effort Based on Use-Cases - Experiences from Industry”, The Unified Modeling Language.Modeling Languages, Concepts, and Tools, 4th International Conference, Toronto, Canada, October 1-5, 2001, LNCS 2185
4. Roy Clem, Project Estimation with Use Case Points, http://www.codeproject.com/KB/architecture/usecasep.aspx
UCP
USP
Object-Orientated
UML
Waterfall
Multi-paradigm
Agile
Use Cases
User Stories
USP - STEP 1PRODUCTIVITY FACTORS
PRODUCTIVITY FACTORS
Total Impact
= Σ(F1..8 weight * F1..8 score)
P FACTOR
PF = 1.4 + (-0.03*Total Impact)
USP - STEP 2USER STORY COMPLEXITY
COMPLEXITY FACTORS (1/2)Weight Name
2 Distributed or Parallel processing
2 Concurrency or Synchronisation
2 High Performance
1 Reusability & Modularity
1 Complex internal Processing
COMPLEXITY FACTORS (2/2)Weight Name
0.5 Ease of Use
1.5 Cross-Platform Support
0.5 Complex Setup or installation
1 Extensibility & Compliance
1 Security
USER STORY COMPLEXITY
Complexity Score (USCS) = 5 + Σ{Weights}
USER STORY POINTS
USP = USCS * PF
Example: Shopping app
Estimate during planning meeting. Whole team participates.
PRODUCTIVITY FACTORS
Name Weight Score Impact
Project Familiarity 1.5 4 6
Application Experience 0.5 4 2
Programming paradigm experience
1 2 2
Team Cohesion 1 4 4
PRODUCTIVITY FACTORS
Name Weight Score Impact
User Story Robustness 1.5 5 7.5
New / part-time team-members
-1 3 -3
Programming language complexity
-1 3 -3
Motivation 1 5 5
TOTAL IMPACT = 20.5
P FACTOR
PF = 1.4 + (-0.03*20.5)
= 0.785
User Story
Epic: “As a user, I want to backup my hard drive.”
Story: “As a power user, I can specify files or
folders to backup based on file size, date created and date modified.”
USCP = 7
USER STORY POINTS
USP = 7 * 0.785
= 5.495
=~ 5.5
USP ADVANTAGES
● Objective
● Consistent
● Analytical
● Adaptable to change
WORKSHOP
● Detailed case scenarios
● Velocity
● Ideal Sprint
● Forecasting
“The greatest gift is the power to estimate
things at their true worth
Francois de la Rochefoucauld
Discussion, suggestions, feedback
https://muut.com/usp-estimation
