ABSTRACT
Life-cycle civil engineering involves decisions concerning the design, operation and maintenance of civil engineering works, but such decisions are not always dependable because they are inevitably based on uncertain information, including uncertain risk estimates. Risk-informed decision-making is dependable only if it produces decisions that would also be acceptable if the true risks were perfectly understood and known. The term ‘fiducial confidence’ has been used to refer to the level of confidence that a decisionmaking process is dependable, and this paper discusses the concept of fiducial confidence in relation to decisions based on probabilistic measures of life-cycle performance. A new fiducial confidence function https://www.w3.org/1998/Math/MathML"> G X x 0 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429227196/8b5c0a5d-ddea-4c88-8eea-7152f7afb008/content/eq14956.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> is defined as the proportion of the expected value of a risk metric X that is attributable to uncertain outcomes where the risk does not exceed an estimated value https://www.w3.org/1998/Math/MathML"> x 0 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429227196/8b5c0a5d-ddea-4c88-8eea-7152f7afb008/content/eq14957.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> . The fiducial confidence function is used to assess the effects of uncertain probabilities of failure and expected costs for designs based on prototype testing. It is shown that uncertainty in risk estimates can have a significant effect on the confidence engendered by their use in decision-making.
