We introduce a simple financially constrained production framework in which heterogeneous firms and banks maintain multiple credit connections. The parameters of credit market interaction are estimated from real data in order to reproduce a set of empirical regularities of the Japanese credit market. We then pursue the metamodeling approach, i.e. we derive a reduced form for a set of simulated moments \(h(\theta ,s)\) through the following steps: (1) we run agent-based simulations using an efficient sampling design of the parameter space \(\Theta \); (2) we employ the simulated data to estimate and then compare a number of alternative statistical metamodels. Then, using the best fitting metamodels, we study through sensitivity analysis the ...