A software-supported process for assembling evidence and handling uncertainty in decision-making

Complex socio-technical decisions, such as infrastructure investment decisions, are based on large quantities of evidence assembled and manipulated by multi-disciplinary teams. Information about decision options and future states of nature will often be ambiguous, incomplete or conflicting. In this article, a software-supported approach to assembling, structuring and representing evidence in a decision, based on hierarchical modelling of the processes leading up to a decision, is presented. Uncertainty in the available evidence is represented and propagated through the evidence hierarchy using Interval Probability Theory (IPT), providing a commentary on sources and implications of uncertainty in the decision. Case studies in the oil and civil engineering industries demonstrate how the approach has helped to develop shared understanding of the implications of uncertainty. It has enabled experts to externalise their knowledge and has facilitated discussion and negotiation.