Previously, a patch was selected by the total 'benefit' achievable by fishing there. It considered biomass beyond the capacity of a vessel in the decision making process. This implicitly incorporated some sort of 'catchability' in that patches in which density was higher were more likely to be chosen. However, this also resulted in behavior that force fishers to select patches that were far from port and when capacity was very low and costs high, profits might be negative.
I 'fixed' this problem by capping the 'benefits' matrix at the capacity of a boat. This allows a fisher to fish close to home when there are fish available, but removes the 'catchability' functionality. There needs to be some function for scaling the 'benefits' in a patch by the density, but it is currently unclear to me how this should be done.
Previously, a patch was selected by the total 'benefit' achievable by fishing there. It considered biomass beyond the capacity of a vessel in the decision making process. This implicitly incorporated some sort of 'catchability' in that patches in which density was higher were more likely to be chosen. However, this also resulted in behavior that force fishers to select patches that were far from port and when capacity was very low and costs high, profits might be negative.
I 'fixed' this problem by capping the 'benefits' matrix at the capacity of a boat. This allows a fisher to fish close to home when there are fish available, but removes the 'catchability' functionality. There needs to be some function for scaling the 'benefits' in a patch by the density, but it is currently unclear to me how this should be done.