So previously I posted that factors outside our own control make accurately estimating the total test schedule impossible. In addition, I posted that even estimatingf simple, known, static things by breaking them into tasks, then adding up the tasks is much less accurate than you might think.
Imagine your typical workday that ends at 5:00 think about it. Sure, I'll likely be home from my drive at 5:30, but I might hit traffic, my boss might ask me a question at 4:55PM, someone in the parking lot might need a jump start. So if you want a commitment from me to predict when to invite the neighbors of when to pull the turkey out of th oven, I should likely say 6:00PM.
That's a 100% timing padding.
One hundred per cent.
On a task I've done hundreds, if not thousands of times with known physical 'resources' and very few dependencies.
Which reinforces the conclusion that test accurate estimation is impossible. At least in the sense of estimating a single number for total time without context.
Yet we are tasked with doing it anyway -- better yet, creating that context. So where do we start?
About a year ago my good friend Ben Simo pointed out to me that even if you know nothing at all about a project, you can always estimate it. Here's an example:
Q: "How long will testing take?"
A: "Two Weeks."
See that? I know absolutely nothing at all about the software. Nothing at all. But I made up a number.
For any given project, we likely know more than nothing. So we can certainly do a better estimation than "two weeks."
Next: I'll start talking about how I do that.
Schedule and Events
March 26-29, 2012, Software Test Professionals Conference, New Orleans
July, 14-15, 2012 - Test Coach Camp, San Jose, California
July, 16-18, 2012 - Conference for the Association for Software Testing (CAST 2012), San Jose, California
August 2012+ - At Liberty; available. Contact me by email: Matt.Heusser@gmail.com