How big is your Story Point? No, I don’t mean in hours, we all know that a Story Point to Hours comparison is impossible. I mean, when you estimate how long a User Story might take, how do you decide on the number of Story Points? What’s your yardstick?
Estimating by Comparing in the Middle of a Project
Probably the easiest way to estimate a new story is to compare it against the other stories that you already have in your Product Backlog. A really good way would be to have all of the current stories sorted into Story Point columns. So, for example, all of the 2 Story Point User Stories in one column, all of the 3 Story Point User Stories in another column and so on. Now it’s just a case of seeing which column the new story naturally fits in.
Estimating by Comparing at the Start of a Project
However, if you’re at the start of your project and there’s nothing to compare with, don’t despair. The easiest way to address that situation is to identify the two stories that are at opposite ends of the scale and then gauge all of the other stories between these two end points. I tend to use the columns idea again, providing columns for Story Points in an adjusted Fibonacci sequence, stopping at 13 Story Points with a final column titled ‘Epic’. This final column acts as a place holder for stories that need to be broken down into multiple User Stories of 13 Story Points or less.
One word of caution about this. Ensure that the large story you use is not an unsizeable epic to which you attach an arbitrary large estimate. They’re unreliable.
How You Can Measure Your Story Point
Once you have your two endpoints, you have your measure or, your yardstick. Use it whenever you need to provide a new estimate or review your current estimates, for example during Product Backlog Grooming