Taking uncertainties into account
Reliability block diagrams

The use of DDBs is so powerful that it allows parameter uncertainties to be taken into account in BDF calculations.

For figure 31 , the parameters λ _E , λ _F and λ _G of the 2/3 system with detected failures are no longer known precisely, but with some uncertainty. This is equivalent to considering them as random variables characterized by probabilistic distributions, as shown on the left of figure 31 .