A core component of the management strategy evaluation (MSE) process that represents the “true” underlying status and dynamics of the population, fishery and monitoring regime. There will be a number of OMs considered so as to capture the full range of uncertainties applying to the resource and fishery. Often two sets of OMs are used: a “reference set” of the most plausible scenarios/hypotheses with the greatest impact on outcomes, and a “robustness set” of unlikely, but still possible scenarios/hypotheses.
