Scrum and Fibonacci

In a prior post we reviewed the way in which you can live in Quadrant 2 via encouragework's Issues feature.

As a quick re-introduction, the Issues tab is organized on a per-team basis and allows team members to put issues into a "parking lot" for discussion at an appropriate time. Once each Issue is discussed, the Issue might be simply closed out, or one or more ToDos may be associated with it to move it closer to a satisfactory resolution.

Now, how do we prioritize Issues so that we know what to work on next? Value is defined as the Benefit divided by the Cost.

Excellent. So what are Scrum and Fibonacci and what do they have to do here?

Let's start chronologically by looking first at Fibonacci.

Fibonacci was an Italian mathematician who introduced us to much of what we think of as "numbers" and "math" today. Yes, there are many other contributors, and you can learn about them in the two excellent books Men of Mathematics by E.T. Bell and Mathematics: is God Silent? by James Nickel. What is of particular interest to us is the "Fibonacci Series." Fibonacci did not invent this as much as he discovered it. 

The Fibonacci series is a sequence of integers which starts with "1 1." Every subsequent number in the series is equal to the sum of the prior two values:

1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233

Neat. But what do we do with those numbers? That is where Scrum comes in.

Scrum is a term that comes from rugby "get togethers" that has been adopted by Agile practioners.

In his excellent book entitled Scrum, Jeff Sutherland talks about how difficult it can be to estimate on a linear scale (i.e. the way we were taught, on a scale of 1 to 10). However, we tend to do a better job of making "relative" comparisons. This is where the Fibonacci series comes in. Rather than estimating the benefit or the cost of something on a linear scale, try using a scale consisting of the first handful of numbers from the Fibonacci series.

Just as an example, in the table below we look at the relative "costs" of various home improvements we might make to help sell our home.

Cost Score Comment
1 Clear the table after dinner. No one wants to see dirty plates on the table!
2 ...and vacuum the floor in the kitchen.
3 ...and vacuum every room in the house.
5 ...and repaint the kitchen. Get rid of that old blue!
8 ...and paint the lower level. It's time!
13 ...and paint the entire house. Yeah, the bedrooms too.
21 ...and replace the carpets. Shag is no longer in style?
34 ...and paint the exterior of the house and put in a new bay window in the dining room. We want to show off the great backyard!
55 ...and replace all windows in the house. Energy efficiency!
89 ...and blow out the dining room wall and add a sun room off the back with a new master bedroom and bath above. Luxury!
144 ...and add a swimming pool with wrap-around patio. And a sauna. And a fire-pit. Recreation!
233 Tear down the house and rebuild it from scratch. Just start over.

Relative numbers do a better job of capturing cost than a simple linear scale. It takes some practice and some calibration, but before long your team will get a sense of what a "34" looks and feels like. 

This approach is useful for both estimating benefit and cost. Here are some examples for "Value" you might see in encouragework as you record your own Issues:

Benefit Cost Value (x100) Comment
1 34 2.9 Low value; probably not worth our time!
13 5 260 Likely worth tackling; very typical value.
34 55 61.8 Non-trivial value, but with some effort. Give it serious consideration.
89 3 2967 Yes, you are going to do this!
1 1 100 If you don't enable "Value tracking," all of your issues will default to benefit = 1, cost = 1, value = 100

In order to take advantage of this "Value" feature for your Issues management, edit the Group settings by clicking on the pencil icon and then checking the option labeled "+ Issue Tracking 'Value' Entry."

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