Optimism Bias - Developing the Evidence Base

The aim of this research is to update the evidence base for the Optimism Guidance in WebTAG. The current guidance has come under scrutiny for being outdated as it fails to capture specific characteristics, complexities, and risk profiles of schemes as well as depending on datasets from 2002. This research project will acquire current cost datasets from various departments and organisations in order to update Optimism Bias uplift values.