Thursday, July 17, 2014

My research into finding a better way to estimate lead down many paths. Many had no real, concrete, empirical way to go about estimating. Others cautioned away from it completely. While I'm in no seat at this point to impart supreme wisdom, I can share something I did find insightful.

COCOMO II

function point analysis

With COCOMO II I learned much about different factors that can impact delivery. This model attempts to include those, combined with the size of the software in order to plot effort distribution. The reason I found this insightful is because it calls out effort that I and others never really seem to recognize.

For an example, let's try this exercise with three fields and a button. Save the fields, send an email, and display some data to a user.

With function point analysis we can quantify the requirements as function points. Let's use this premade spreadsheet to make it easier to do our experiment.

http://www.cs.bsu.edu/homepages/wmz/funcpt.xls

I use 4 simple inputs, 2 user outputs (email and display to user), 1 inquiry (the return data), and 3 files (the data tables, the email builder, the response page). I tried to be conservative with Fi.


then, we plug our number into the calculator. (in this case 136) or rather let's reduce that by the ILFs and take 136 - 90 or 46 to be conservative since I'm slightly unsure about the ILFs at this time so I'll write them out of the equation completely, after all we're experimenting.


make our scale and driver adjustments as necesary (let's keep these default for now.

 and the tool runs the data through the model and shows us the light.


Who would have thought that three fields and a button could take so much effort? Sure we can take shortcuts and get it done in a day, but that comes with much future risk because of the likelihood of creating mounds of technical debt - especially over time when this sort of wild-west thinking becomes the normative.

There are several sources out there with full descriptions about how the model works. It's all very scholarly and technical. Why does this matter? This is important because it's something you can show managers that will give them the same insights as you gained. Arm them with information about technical debt management and you are on your way to a more realistic reality! Unless they are unwilling to learn, grow, change, listen to scholars or naval research. In that case, start shopping for new opportunities.

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