Dates and deadlines are an essential human element of project management. People work better if they have challenging but realistic schedules to work against.
The trick is “challenging but realistic.” In software, we know there is wide variation in our estimates, because we are almost always creating something unique (if it’s been done before, we just copy the bits). And we have a systemic underestimation bias, because there are lots of ways to cut scope or cut corners in software, and the intangible nature of it all makes anything seem possible.
Unfortunately, when schedules are no longer realistic, it will quickly destroy a project: causing cynicism, demotivation, short-cuts, bad decisions, unwillingness to respond to new information, loss of honesty and trust, and other problems which will fester. We could avoid these pitfalls if only we could estimate better. There are good books on this, including McConnell’s Software Estimation: Demystifying the Black Art and Wiegers’ Practical Project Initiation
.
Out of all the techniques covered in those books, one widely-used technique is particularly effective for those critical early estimates of large, not-yet-well-understood projects. Estimates upon which we base our go/no-go decisions and early expectation-setting for upper management and customers.
It’s called Wideband Delphi, and here is a simple spreadsheet template and guide for the Wideband Delphi technique. Take a look, and let us know if this is useful to you and your groups.



Kanban discussion
Kanban Group
James Waletzky | 26-Feb-08 at 12:09 am | Permalink
Wideband Delphi is in use at Microsoft by quite a few teams and is a great estimation technique to improve accuracy early in the project cycle.
Here are a couple more sources containing more information on Wideband Delphi:
- Progressive Development blog posting (http://blogs.msdn.com/progressive_development/archive/2007/09/25/motley-says-individual-gut-feel-estimation-is-the-only-way-to-estimate.aspx)
- MSDN article (http://msdn.microsoft.com/msdnmag/issues/07/01/EndBracket/)
- Wikipedia entry (http://en.wikipedia.org/wiki/Wideband_delphi)
Bernie Thompson | 26-Feb-08 at 10:45 am | Permalink
Great Links, especially like the {End Bracket} article in MSDN. Thanks James!
Ian Cooper | 27-Feb-08 at 8:57 am | Permalink
Have you tried Planning Poker. It’s a great tool for doing wideband delphi. Cards are just easier than a whiteboard. YMMV.
Bernie Thompson | 27-Feb-08 at 12:36 pm | Permalink
Great point, Ian. Planning Poker is really a light form of Wideband Delphi.
http://en.wikipedia.org/wiki/Planning_poker
Have been happy every time I’ve used it.
It’s great for more quickly running through a longer list of smaller projects, like a Product Backlog in Scrum.
Whereas Wideband Delphi (which prompts for more time, dialogue, and simple whiteboard/spreadsheet tool) is better for larger estimates.
Agile Management by David Anderson | 01-Mar-08 at 10:17 pm | Permalink
Announcing Modus Cooperandi…
26 years ago I started my first business working with 3 school friends developing and selling computer…