Fault Tree Analysis (FTA) and Cause &Effect diagram (fish bone) are very similar in some of the cases.
They have some pros that combined could result into a better tool.
FTA provides so much value information:
- Logical dependency between causes (AND, OR)
- Probability of occurrence of a cause expressed on %
Fish bone diagram categorizes the causes by category, and this helps to look to the issue from many different points of view.
If we combine them we could have something like this:
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