The Best Estimating Technique

When you think of estimating and planning techniques, what method do you think of first?  Do you use a parametric technique, Monte Carlo simulation, or something else?  I was over at the Implementing Scrum website and found an awesome post, asking this same question.  If you think people get crazy whether or not you should utilize an Agile approach or a traditional project management approach on a project, wait until you talk about how to estimate work.  In the traditional project management world, I've seen people use SLOC and PERT to arrive at an estimate.  In the Agile world, I've used story points and have seen others use gummy bears and t-shirt sizes. In the end, I really don't care what estimation technique is used and I'm pretty sure the customer won't either.  All anyone should be worried about is if the estimates are accurate and if you get the work done.  Am I right or am I wrong?  I would love to read your input.

Thank you to Mike Vizdos for letting me use his cartoon and for the inspiration for this post.

The Story of Monte Carlo

Once upon a weekday meeting, I had a story to tell.  It was the tale of a project manager, who’s name really rings a bell. He quantified the total project cost, he didn’t miss a dime. He also computed the schedule, he was always aware of the time.

He used all these input values, with random amounts being his friend. He ran these simulations.  I thought they would never end.

The outcome was a distribution, a bell curve if you like.  On the edges we saw some low points, in the middle there was a spike.

Monte Carlo was this fellow’s name, he was a heck of a numbers guy.  We asked him if he ever made things up.  He said he would merely quantify.

Now don’t think Monte worked alone, he had a counterpart.  Her name was Jane Stake-Holder, he worked with her from the start.

Jane could be quite demanding, sometimes ignoring project scope.  But Monte managed the situation well, knowing creep was a slippery slope.

His technique was well documented, a change would make everything slip.  He told this to Jane Stake-Holder who you'd think would do a back-flip.

But numbers don't lie and neither did he, Jane knew Monte would put up a fight.  She backed down and submitted a change request, the schedule would extend to the right.

Graphic: Pictofigo