This video extends the discussion of the preceding video, while laying the foundation for ensuing videos. It explains how calibration based on manual regularization, whether performed automatically by software such as PEST or done manually by a modeller, may fail to find a parameter field that is of minimized error variance. It also shows that calibration achieved through manual regularization does not provide a good foundation for post-calibration uncertainty analysis. This is because the relationships between estimated and true hydraulic properties cannot be resolved when regularization is undertaken manually. The “cost of uniqueness” cannot therefore be assessed.
Presented by John Doherty