Skip to main content

Story Points - what's with the missing numbers?

First let's talk about Numbers, then something else, and then Story Points.

Number, integers and real numbers provide the scientist with a very valuable tool, a continuum of regular spaced labels for comparison purposes.  These integers are sequential with no gaps or voids.  This is quite special in nature, for there are very few things in the natural world that are so regular and consistent over an infinite range.

Let's look at the number 10.  It's a nice round number (divisible by two) and it has a roundness to it's drawing.  It is a commonly used end point in quizzes and surveys.  Is there something special about it - why not use 12?  Chicken farmers do, bakers do, why don't we in the Agile software world?  No - we use unlucky 13.


Something else - Font Sizes
What's your favorite font size?  I'm betting 12 point.  Because it is the default on most software programs - I'll wait take a look.  While you're up there at the font menu where is font size 13?  Maybe right there below 12.  Where is size 15?  On one of my favorite tools the drop down goes 8, 9, 10, 11, 12, 13 14, 18, 24 ....

What's wrong with 15 point?  And why are all those other numbers missing?

While we're talking fonts, I remember back in the early 1990s teaching people about fonts, font styles, and font sizes.  Back then we had more choice.  One typically entered font size in a free form text box, you could have any size you thought might be pre-loaded on your computer.  Fonts were static in size and not scalable (TrueType).  There was a lot to learn about fonts.  What's a point?  Well it turns out I know what a point is:  and 72 of them can dance on a ruler within the tick marks of any inch.

Story Points the missing numbers
Agilist typically use a range of numbers with gaps to describe XP User Stories effort estimates (size).  One common set of numbers is the Fibonacci Sequence, or a modified Fib-Sequence (fib as in lie).

 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...  (Fibonacci Sequence)
 1, 2, 3, 5, 8, 13, 20, 40, 100, 200, ...  (the Fib-Sequence)

Mind the Gap please.  Well are you OK with not finding the 15 pt Font Size?  Then why do you get so concerned about a few missing story point sizes.  It's the same damn thing.  Nobody wants to use font size 34 or cares about the difference between the 12 point story and the 11 point story - just call them all 13 points and move right along, nothing to see here folks.

Why did Agilist choose this particular sequence when the doubling sequence would work also, or the old school cooking measurement system of teaspoons to cups (48 = 1), or pints, quarts, gallons (8=4=1).  Or teaspoons, tablespoon, cups, pints, quarts, gallons ( 768=256=16=8=4=1).

One reason is the utter simplicity of the Fibonacci sequence and that it is an additive system of relative measures.  The sequence is granular at one end and smooth at the other.

If the opposite of granular is smooth, then which end of the Fibonacci Sequence is smooth and which granular?  Why does granular have a small connotation?  I think this is why I don't like the word granular - it's ambiguous when typically used.

Let's recap - in the 1970s it was the metric system, in the 1990s it was the Font Size, and now in the 2010s it's Story Points.

Now remember - without something to compare your story to... it's not relative.  Don't make the same mistake as Edwards.  He had ONE JOB.



Post a Comment

Most Popular on Agile Complexification Inverter

Exercise:: Definition of Ready & Done

Assuming you are on a Scrum/Agile software development team, then one of the first 'working agreements' you have created with your team is a 'Definition of Done' - right?



Oh - you don't have a definition of what aspects a user story that is done will exhibit. Well then, you need to create a list of attributes of a done story. One way to do this would be to Google 'definition of done' ... here let me do that for you: http://tinyurl.com/3br9o6n. Then you could just use someone else's definition - there DONE!

But that would be cheating -- right? It is not the artifact - the list of done criteria, that is important for your team - it is the act of doing it for themselves, it is that shared understanding of having a debate over some of the gray areas that create a true working agreement. If some of the team believes that a story being done means that there can be no bugs found in the code - but some believe that there can be some minor issues - well, …

Elements of an Effective Scrum Task Board

What are the individual elements that make a Scrum task board effective for the team and the leadership of the team?  There are a few basic elements that are quite obvious when you have seen a few good Scrum boards... but there are some other elements that appear to elude even the most servant of leaders of Scrum teams.









In general I'm referring to a physical Scrum board.  Although software applications will replicated may of the elements of a good Scrum board there will be affordances that are not easily replicated.  And software applications offer features not easily implemented in the physical domain also.





Scrum Info Radiator Checklist (PDF) Basic Elements
Board Framework - columns and rows laid out in bold colors (blue tape works well)
Attributes:  space for the total number of stickies that will need to belong in each cell of the matrix;  lines that are not easy eroded, but are also easy to replace;  see Orientation.

Columns (or Rows) - labeled
    Stories
    To Do
    Work In P…

Webinar: Collaboration at Scale: Defining Done, Ready, and NO.

I was invited to participate in a Scrum Alliance Webinar.  Maybe you would like to listen to us in a discussion of techniques to collaborate at scale (remotely and with many people).  The topic is one that I've got some experience in discussions - yet I never seem to get to done...
Collaboration at Scale: Defining Done and Ready and NO for Distributed Teams
With Joel Bancroft-Connors, Agile Organizational Coach; David A. Koontz, Agile Transition Guide; and Luke Hohmann, CEO and Founder of Conteneo, Inc.


14 February 2018 11 a.m. ET (USA).




The Scrum Guide is pretty clear on the criticality of the definition of Done: "When a Product Backlog item or an Increment is described as "Done," everyone must understand what "Done" means. However, the Scrum Guide ALSO says that the definition of Done can "vary significantly per Scrum Team." This leads us to examine when and how the definition of Done should vary, how distributed teams should cr…

A T-Shaped 21st Century Knowledge Worker

Knowledge workers in the 21st Century must have many areas of deep knowledge, while also be capable of collaboration across multiple other domains with dissimilar T-shaped individuals.  This description of a person is a metaphor.  Compare it to the shape of the "I" in the classic saying there is no "I" in Team.


I first read about Scott Ambler's term "Generalizing Specialist" - but it's so hard to remember the proper order of the words... get it backwards and it has an inverted meaning... T-Shaped is easier to remember. 
A generalizing specialist is someone who:
Has one or more technical specialties (e.g. Java programming, Project Management, Database Administration, ...). Has at least a general knowledge of software development. Has at least a general knowledge of the business domain in which they work. Actively seeks to gain new skills in both their existing specialties as well as in other areas, including both technical and domain areas.  General…

A FAILURE to Communicate

I was working with a failing team some time ago.  I use "failing" to describe the outcome of the team - not the people on the team.  Are you OK with that description?



An issue arrose in the stand up - a team member that was to verify the quality of a procedure did so and reported that there were a few records that didn't match expectation in the data set.  Upon inquire the number of records not matching was over 2000.  Most people acknowledged immediately the exaggeration - I could tell by the laughter.  After about 10 minutes of discussing the details of the problem - it appeared the team had a handle on the specific situation.

I stopped the discussion and inquired if they could name the impediment.  One team member did a great job of describing the impediment as a _communication gap_.  Wonderful - I could work with that - the problem had a name and it didn't include anyones Proper Name.

"If the problem has a first name; we are going to have a problem."

I&#…