The ADMB framework is first tested on cod (Gadus morhua) data. In the first step, we start with a simple model, defined by [1] and an objective function defined by [2]:
N_t = N_t-1e^-M - C_t [1]
f(s,q_t) = (2s²)^-1[ln(q_tN_t)-ln(I_t)]² [2]