fast and frugal tree for product importance Rikard Edgren

Software testing is difficult because there are so many possibilities; not only all functions and their interactions and attributes, but also possbible users’ data, needs, environments and feelings.

Good software testing need to deliberately sample, and understand what is important.
This understanding that evolves over time give testers an intuition about which tests to run, which spurious behavior to investigate, and which bugs need emphasis.

Gerd Gigerenzer describes in Adaptive Thinking his theory (that originates from Herbert Simon) that intuition is based on heuristics, that we are using fast and frugal decision trees in order to make good judgments in a complex world, with limited information.

This is my decision tree for judging software importance:

Fast Frugal Importance Judgment

Fast Frugal Importance Judgment

Use an expansive definition of user if you want to capture issues like Supportability, Testability, Maintainability.
Or even better, write your own tree, and notice the differences in your project, differences you might benefit from.

Darren McMillan February 15th, 2011

Hi Rikard,

This is very good, I like it a lot! I can see real benefits in these for training new testers quickly, when pairing is not an option.

Very good, thanks for sharing.



Rikard Edgren February 16th, 2011

Thanks Darren.
There is nothing spectacular about these, but they are seldom expressed, since they are obvious/intuitive.
Maybe they can be easily learned and adapted in a format like this.