Wideband Delphi is a reliable estimation techniques that is prepared based on team consensus. This presentation discusses the process and includes examples, which can be followed when preparing your own estimates.

1. Wideband Delphi Technique
George Ukkuru

2. Introduction
Consensus based approach for estimation
Developed in the 1940’s at Rand Corporation
Team of experts prepare individual estimates.

3. Benefits
Build a complete task list or work breakdown
structure for major activities.
Consensus approach helps eliminate bias in
estimates.
Eliminate hidden agendas or divergent objectives
for inexperienced estimators or influential
individuals.
Does not require historical data to prepare the
estimates.
Straightforward and Repeatable process

4. Process

5. Planning
Project Manager selects a team and a
moderator
Team consists of 3-7 team members
Representation from all groups like
development, testing etc
Moderator to be familiar with the Delphi process
Ideal to have the Project Manager as a part of
estimation team
Project Manager should not be the moderator as
he will have stake in the outcome of the
estimation

6. Kickoff Meeting
Explain the Delphi process
Read the vision and scope document or any
supporting documents [Pre-requisites]
Review the goals of the estimation session
Brainstorm and note down the assumptions
Generate the initial WBS
Decide upon the unit for estimation

7. Individual Estimation
Estimate the time required for each task
Add any additional tasks to the WBS
Add any missing assumptions

8. Estimation Meeting
Moderator shares the estimates so that
estimators can see the range of estimates
Individual estimates are not shared
Team members revises estimates based on
group discussions
Estimates are revised until no estimator wants to
changes his/her estimates.
Estimators agree that the estimates are
acceptable.

9. Wide Band Delphi Example
There estimators A,B and C are told to prepare the time
required to prepare test scenarios for a project
The initial estimations provided were
A – 18 Hours
B – 38 Hours
C – 58 Hours
The moderator then
Calculates average estimate as 38 hours
Returns this with their original estimates to the
estimators

10. Wide Band Delphi Example
The estimators then meet and discuss the estimates
The initial estimations provided were
A – 31 Hours
B – 32 Hours
C – 33 Hours
The moderator then
Calculates average estimate as 32 hours
Asks the estimators if they agree with this as the
estimate

11. Iterations in Estimations
Round 2 X X X
Round 1 X X X
10 20 30 40 50 60

12. Assemble Tasks & Review
Results
Project Manager works with the team and
collects the estimates from team members
Compiles the final WBS, estimations and
assumptions
Reviews the final estimates with the estimation
team

13. Ground Rules
All estimation sessions must be performed
individually with no group interaction
Estimators must indicate factors affecting their
estimates
Estimators will ignore holidays, vacations and
other similar factors
Anonymity must be observed during the whole
estimation process
Estimation sessions should have a predefined
time limit

14. Assumptions
Assume that one person will perform all tasks
Assume all tasks will be performed sequentially
Assume that you can devote uninterrupted time
to each task

15. About the Author
 George Ukkuru is working as a test manager with UST
Global Trivandrum. He is having more than 10 years of
experience in the field of software testing. He holds various
certifications like PMP,CAPM,CSTE etc. He can be
reached at ukkuru@gmail.com