Estimation with Use Cases: Deeper Thoughts

I came across a thought provoking white paper written by John Smith of Rational Software. It's on Estimation of effort based on Use Cases.

If you have ever tried estimation with use cases, you know that the various levels of decomposition encountered in the wild are troublesome. John does an excellent job in conceptualizing this problem.

The article seems to be from 1999, and I'm not sure whether John's ideas made it into the various estimation tools. For me, reading them brought a great deal of clarity in the levels-of-use-cases concept, so I think it's worth reading anyway.

Understanding the exponential function

I was pointed to a set of videos that explores the exponential function and what most people think about its consequences. Seems to be a boring topic.

It isn't. I watched the first 10 minutes, only to realize my jaw has dropped to the floor. This is stuff I knew and didn't grasp at the same time. I strongly suggest you invest the ∼75 minutes and watch it.

It hit me two days after I started to drivel about me liking sustainable solutions. I wasn't up to all my senses, obviously. ;-) 

Estimating with Use Case Points - FREE template

Being lazy, I was looking for a free, read-made, comprehensive and easy-to-use spreadsheet template for estimating project effort with use case points. I needed it for one of my current projects, in which we are writing 200+ use cases (sic!, see my remark below), and prepare a project proposal for senior management. 

I came across Scott Selhorst's material on Use Case Point Estimation. Very useful!

Check out:

• An introduction to use case point estimation with good context for use case newbies
  
• A How-to for the final calculations
  
• The free template
  

The template can also be googled and found at modernAnalyst, another useful source of information for business analysts and such folk.

Note on the large number of use cases: I personally think they are no real use cases. It's quite close to a functional decomposition done in use case form. I expect the system to arrive at about 8000 Function Points, but estimates range from 1.000 to 15.000 as of now :-)

 

Templates available in GERMAN

I translated two kinds of templates to German, in case you need them in that language.

• A template of an impact estimation table
• A set of 3 requirements templates for functions, scalar requirements and designs.

Both is Tom Gilb's work, although I took the table from Ryan Shriver.

Impact Estimation Table Template for free download

Courtesy of Ryan Shriver I translated his Impact Estimation Table template into GERMAN. Go here to download it.

The above link to the german table will also give you a glimpse on the Wiki project I'm doing: All the posts, i.e. principles, process and rules will be available in a wiki format shortly.