Integrating Collaborative Requirements Negotiation and

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Integrating Collaborative
Requirements Negotiation and
Prioritization Processes:
A Match Made in Heaven
Nupul Kukreja
Annual Research Review
14th March 2013
Outline
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• Motivation
• High-level overview
• Background and Related work
• Two-step Prioritization Approach
• Evaluation and Results
Motivation
• Not enough time and money to implement
all requirements
– Need to prioritize requirements w.r.t. budget and
schedule constraints
• High coordination and transaction costs to
ascertain requirement priorities or reprioritizing
new/changed requirements
• Too many ties using MoSCoW or 1-10 scoring
– Assumes stakeholders can correctly score
requirements as per intrinsic value
– Difficult to ascertain value of new/changed
requirements in relation to others
Solution
Value-Based Requirements Prioritization (VBRP)!
• Stakeholders select the most valuable requirements for
implementation
– “Value lies in the eyes of the beholder” – but can be
captured with some effort
• Decision theory folks working on this for a long time
– Some models (e.g. AHP) have been used for requirements
prioritization with varying degrees of success
• Propose a ‘lightweight’ two-step approach based on
TOPSIS (Technique of Ordered Preference by Similarity
to Ideal Solution)
Two-step Approach – Overview
Decompose
System into
MMFs
Prioritize w.r.t.
business goals
(TOPSIS)
Decompose MMFs
into low level
requirements
Prioritize w.r.t.
business value,
relative penalty &
ease of realization
(TOPSIS)
TOPSIS (What?)
Alternative 1
Ideal Alternative
(S’)
Criterion 1
Non-Ideal
Alternative (S*)
Alternative 2
Criterion 2
Aim: Rank order alternatives by their ‘closeness to ideal’ and ‘distance from non-ideal’
Criterion: Has ‘direction of preference’ i.e. more/less of the criterion is preferred
Ideal: Best score for each criterion Non-ideal: Worst score for each criterion
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TOPSIS (Why?)
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Winbook
• A collaborative, social networking based tool
for requirements brainstorming similar to
facebook…
• …with requirements organization using colorcoded labels similar to Gmail…
• …to collaboratively converge on software
system requirements reaching win-win
equilibrium (based on Theory-W)…
• …by keeping it short and simple like XP’s user
stories!
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TOPSIS integrated with Winbook in v2.0
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TWO-STEP PRIORITIZATION
0. Goals Articulation & Prioritization
• WinWin methodology assumes project goals
are captured and prioritized before
commencing “WinWin Negotiations”
• Added a “precursor” step for capturing and
prioritizing goals prior to initiating
negotiations
• Goals captured in Winbook and prioritized
using success sliders
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1. MMF Decomposition
• Top-down decomposition of system into
Minimum Marketable Features (MMF)
– Units of software value creation
– Components of intrinsic marketable value
• Prioritize MMFs against project goals:
– MMFs scored against each goal on a 1-9 scale
(1 = MMF has little to no contribution in realizing the
goal; 9 = MMF wholly contributes towards realizing
the goal. Absolute scale okay too)
– MMF priorities ascertained by underlying TOPSIS
algorithm
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MMFs are ‘leaves’ of tree
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MMFs
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2. Win Condition Capture & Prioritization
• Win Conditions (WCs): Stakeholders’ desired
objectives stated in an easy to understand manner
and formalized where necessary (“functional”
WCs captured in ‘user-story’ format)
• MMFs decomposed into constituent WCs
• Win conditions prioritized against:
– Business Value (1: low; 9: high)
– Relative Penalty (1: low; 9: high)
– Ease of Realization (Story-points/Fibonacci scale)
• WCs priorities also computed by TOPSIS and
scaled by MMF they belong to
(Similar GUI as previous slide)
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Two-Step Prioritization
Goals
Success
Sliders
MMFs
Requirements
Goal 1
Business
Value
Goal 2
Relative
Penalty
…
Ease of
Realization
Goal n
: Influences Priority Score
• MMFs influenced by business
goals
• Win condition scores influenced
by MMFs they belong to
• Change in goal weights 
change in requirement priorities
• Dynamically (re)prioritizable
product backlog
• Developers can ‘pull’ most
valuable requirements from
(up-to-date prioritized) backlog
Evaluation & Results
• Two-step approach deployed in software
engineering project course (CS577) @ USC since
Fall 2011
• Empowered teams to perform sensitivity
analyses:
– Varying goal weights and gauging impact on
MMFs/WCs
– Varying criteria weights to ascertain high-value, highrisk or complex WCs for prototyping
• New requirements/changes comparable with
existing ones to ascertain optimum scope leading
to channelized negotiation sessions
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Evaluation & Results (Cont’d)
• Ability to have requirements backlog with
accompanying rationale for each requirement
• TOPSIS-Winbook approach provided significant
improvements in organizing, updating and
accessing captured rationale over previous
versions of the WinWin negotiation systems
• Live traceability from goals to win conditions (and
vice versa) vs. static traceability matrix
– Makes explicit contribution of MMFs to goals (and
consequently WCs to goals)
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Limitations
• TOPSIS rank reversals – inclusion of spurious
alternatives can change prioritization order of
requirements
– Not a major concern for cooperative teams (not intent
on gaming the system)
– Cause of concern for negotiation among competitors
• Hierarchical prioritization may not agree with
intuition/gut-feel
– Teams manually account for discrepancies
• Prerequisites/dependencies not handled in
current version of Winbook
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Conclusion
• Two-step prioritization decouples business
(goals/MMF) prioritization from individual
requirements
• Ability to quickly gauge impact of changing
business goal priorities on individual
requirements
• Provides dynamic reprioritizable product
backlog for use in lean/agile/kanban projects
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Integrating a decision theory based prioritization
framework with a collaborative requirements
negotiation and management tool thus provides
a rationale-backed prioritization of requirements
allowing the stakeholders to channelize their
negotiation and development efforts around the
most valuable requirements.
A match truly made in heaven…
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Thank you!
Questions?
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