Agile Software Development Estimating Experiment

Agile Estimating Experiment.I recently came across this agile estimating experiment by Lance Walton. The article is quite old now but I still found it very interesting…

In recent years, I’ve had quite a fascination with the concept of velocity and estimating in points.

To be honest, it took me quite a while to really get this concept! But once I understood the statistical nature of it – once the penny finally dropped – I have loved it ever since!

In my experience, it really is the secret to delivering on time – the holy grail of software development projects for decades. And better still, it’s so easy to do. Well, fairly!

The biggest obstacle of all seems to be explaining it to people without sounding completely mad. It really does sound quite whacky. Some weird development technique practiced only by people with long beards and sandals! :-)

But it’s worth doing. Because it works!

Lance’s experiement is interesting because he is using statistics to show evidence that estimating user stories in points was just as accurate as estimating tasks in hours. And in his case at least, it was.

I can remember trying to convince some teams to try estimating in points. With so little information, they were convinced that estimating user stories in points wouldn’t be accurate. The truth is they were probably right. Estimating in points isn’t accurate. My argument for using points was somewhat counter-intuitive. I remember saying that points will be just as inaccurate as any other method, but would take less time to do and then they’d have more time to get on with the job!

What is interesting, though, is that when you estimate with relativity using points, and plan future iterations based on past velocity, it’s remarkable how predictable you can be. Even with very little information at the point of estimating.

If you’re interested in this topic, you can read more from me here: agile estimating


Photo by Haria Varlan

2 Responses to “Agile Software Development Estimating Experiment”

  1. Anonymous says:

    I've read the paper you referenced and it doesn't appear to say that the team estimated their stories in points. The author mentions "points" but he is speaking about data points on charts rather than estimation units. I think the "point" of the experiment was to show that story level estimates (presumedly in hours) were reasonably accurate without breaking the stories down into tasks and estimating time at the task level.

  2. Oliver McPhee says:

    Hi Kelly,

    I would be interested in reading more about your implementation of this points system ~ Its an interesting area.

    A fun technique i came across recently was 'Planning Poker' for agile estimating.

    How to Play Planning Poker

    Have you tried a wide range of estimation techniques?

Leave a Reply

What is 8 + 10 ?
Please leave these two fields as-is:
Please do this simple sum so I know you are human:)

There are 101 ways to approach anything.
To find the best way, sometimes you need expert help

What People Say

“Kelly revolutionised the way our digital department operated. A true advocate of agile principles, he quickly improved internal communication within our teams and our internal clients by aligning our business and creating a much enhanced sense of transparency in the decisions the business was making. Kelly also introduced a higher sense of empowerment to the development teams...”


“Kelly’s a leading program director with the ability to take charge from day one and keep strong momentum at both a program and project level driving prioritisation, resourcing and budgeting agendas. Kelly operates with an easy-going style and possesses a strong facilitation skill set. From my 5 months experience working with Kelly, I would recommend Kelly to program manage large scale, complex, cross company change programs both from a business and IT perspective.”


“Kelly is an extremely talented and visionary leader. As such he manages to inspire all around him to achieve their best. He is passionate about agile and has a wealth of experience to bring to bear in this area. If you're 'lucky' he might even tell you all about his agile blog. Above all this, Kelly is great fun to work with. He is always relaxed and never gets stressed - and trust me, he had plenty of opportunity here! If you get the chance to work with Kelly, don't pass it up.”


“Kelly is an Agile heavy-weight. He came in to assess my multi-million $ Agile development program which wasn’t delivering the right throughput. He interviewed most of the team and made some key recommendations that, when implemented, showed immediate results. I couldn’t ask for more than that except he’s a really nice guy as well.”


“Kelly and I worked together on a very large project trying to secure a new Insurer client. Kelly had fantastic commercial awareness as well as his technical expertise. Without him I would never had secured this client so I owe a lot to him. He is also a really great guy!”


“Kelly came to the department and has really made a huge impact on how the department communicates, collaborates and generally gets things done. We were already developing in an agile way, but Kelly has brought us even more into alignment with agile and scrum best practices, being eager to share information and willing to work with us to change our processes rather than dictate how things must be done. He is highly knowledgable about agile development (as his active blog proves) but his blog won't show what a friendly and knowledgeable guy he is. I highly recommend Kelly to anyone looking for a CTO or a seminar on agile/scrum practices - you won't be disappointed!”


“Kelly was a great colleague to work with - highly competent, trustworthy and generally a nice bloke.”


“Kelly was engaged as a Program Director on a complex business and technology transformation program for Suncorp Commercial Insurance. Kelly drew on his key capabilities and depth of experience to bring together disparate parties in a harmonised way, ensuring the initiate and concept phases of the program were understood and well formulated. Excellent outcome in a very short time frame. ”


“I worked with Kelly on many projects at IPC and I was always impressed with his approach to all of them, always ensuring the most commercially viable route was taken. He is great at managing relationships and it was always a pleasure working with him.”


“I worked with Kelly whilst at Thoughtworks and found him to be a most inspiring individual, his common-sense approach coupled with a deep understanding of Agile and business makes him an invaluable asset to any organisation. I can't recommend Kelly enough.”


“Kelly was a brilliant CTO and a great support to me in the time we worked together. I owe Kelly a great deal in terms of direction and how to get things done under sometimes difficult circumstances. Thanks Kelly.”