Uncertainty Modeling and Probabilities in Engineering Decision Analysis

The present paper initially gives a basic introduction on the interpretation of uncertainty and probability in engineering decision analysis and explains how in some cases uncertainties may change type depending on the "scale" of the applied modeling and as a function of time. Thereafter it is attempted to identify and outline the generic character of different engineering decision problems and to categorize these as prior, posterior and pre-posterior decision problems in accordance with the Bayesian decision theory. Finally an input is given to an ongoing discussion concerning the correctness and consistency of the uncertainty modeling applied in most recent reliability updating analysis for structural re-qualification and inspection and maintenance planning. To this end an outline is given in regard to the appropriate uncertainty treatment in the probabilistic modeling for different types of decision problems.