Management Option Rank Equivalence is a form of breakpoint analysis that reports the changes in each variable required to change the preferred management option.

When to use

MORE can be used for stress testing of a preferred management option. It is a form of breakpoint analysis, i.e. it focuses on values or scenarios for which a conclusion changes.

A model is used to evaluate performance metrics of management options in different model scenarios (expressed in terms of parameter combinations). A reference model scenario is required, e.g. that best fits historical data.

How

A distance metric is selected to determine the difference to the reference model parameters, e.g. a normalised Euclidean distance evaluates change in parameters relative to their maximum and minimum values.

Optimisation is used to minimise that distance with the constraint that the optimised parameters yield a different preferred management option to the reference model (i.e. reverse the rank of the options).

Pareto Optimal Management Option Rank Equivalence (POMORE) is a variant where the distances for each parameter are optimised separately as a multi-objective optimisation rather than specifying a distance metric. This yields a set of closest scenarios rather than just one.

Selected examples

In a simple flood demonstration problem answering the question "Will regular flooding of ecological assets occur?", POMORE is applied to identify model scenarios where the answer changes.

Resources

Ravalico JK, Dandy GC, Maier HR (2010). Management Option Rank Equivalence (MORE) – A new method of sensitivity analysis for decision-making. Environmental Modelling & Software, 25(2), 171–181. doi:10.1016/j.envsoft.2009.06.012

Ravalico JK, Maier HR, Dandy GC (2009) Sensitivity analysis for decision-making using the MORE method—A Pareto approach. Reliability Engineering & System Safety, 94(7), 1229–1237. doi:10.1016/j.ress.2009.01.009