We just finished estimating a new project at Zest software. With a new method that we all liked quite a lot. It was fun :-)
The basis is of course that you chop up the project in smaller parts. We're using extreme programming, so we call them stories. A story shouldn't be too big, definitively not more than 8 days. We all got a stack of post-its with 1, 2, 3, 5 and 8+ written on them. A story is read and we all put our estimate face-down on the table.
Show the estimate. If there's a big difference, discuss the story a bit more, telling why you think it takes just a day when the rest estimates 5. Or the other way around. Then put in your face-down estimates again, uncover them and take the average.
A fun way of doing estimations. And I think you get real good estimates this way. And yes, 1, 2, 3, 5 and 8+ mean you miss the 4 and so. It forces you to make choices. Which helps (according to my feeling).
My name is Reinout van Rees and I program in Python, I live in the Netherlands, I cycle recumbent bikes and I have a model railway.
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