Does using the Fibonacci series improve the accuracy of estimates?
Marcus UdokangProject Manager| Aivaz ConsultingCalgary, Alberta, Canada
Estimating is hard. Some estimates are easier than others. Absolute difference is not important, relative difference is important. The relative gaps between the Fibonacci series numbers are 0%, 100%, 50%, 66.7%, 60%, 62.5%, 61.5%, 61.8%, 61.8%. The relative gap between the members of the series settles down to about 61% and a bit. Fibonacci series is good for estimating because it encourages us to stay within the realm of easy estimates, using relative estimates. Fibonacci series protects us from making accurate estimates. It allows us to make broad or rough estimates.
Do you use the Fibonacci series for your estimates? Has it been effective? Why or why not? Saving Changes...
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Sergio Luis ConteHelping to create solutions for everyone| Worldwide based OrganizationsBuenos Aires, Argentina
Fibonacci series will not improve accuracy. Nothing will improve accuracy by definition from physic and mathematics. If you take accurancy as a synonim of precision or exactness you are lost. The only thing you can improve is the amount of inherent error. For that, you need information and knowledge. Saving Changes...
I don't think Fibonacci improves accuracy, but Fibonacci is very often associated with relative estimation and I have found that relative estimation improves accuracy (compared to absolute estimation). Relative also has other advantages besides accuracy.
The main advantage of Fibonacci numbers (or more commonly, a modified Fibonacci sequence) is that the task of estimation is simplified by having more coarse-grained estimates as the size increases. Saving Changes...
Marcus UdokangProject Manager| Aivaz ConsultingCalgary, Alberta, Canada
@Sergio, @David, much thanks for the replies. Certainly good points you make.
Marcus Saving Changes...
Drew CraigSr. Agile & Product Coach| VanguardPhiladelphia, Pa, United States
Fibonacci is not to improve accuracy (as depicted in this thread), rather to abstract any notion of time and reflect on the lift needed to complete the work. The relativeness of the Fibonacci numbers helps to also align the team on sizing their work relative to other work. Is it bigger, smaller, etc?
It also facilitates conversation and alignment on the work across the team and additionally identifies gaps or dependencies through those conversations. Saving Changes...
Marcus UdokangProject Manager| Aivaz ConsultingCalgary, Alberta, Canada
