Consider a contract between two players, describing the payment an agent obtains from the principal, in exchange for a good or service supplied. At each point in time, either player may unilaterally demand a renegotiation of the contract, involving renegotiation costs for both players....

We examine optimal harvest policies in a multi-cohort, multi-gear bioeconomic model of North-East Arctic cod (Gadus morhua) which includes cannibalism and contains broader ecosystem effects. By controlling the selectivity of the different fishing equipment, we can partially target different age...