Quantifying the Aggregate Effects of Inter-Firm Knowledge Networks
题目： Quantifying the Aggregate Effects of Inter-Firm Knowledge Networks
This paper evaluates the impacts of inter-firm knowledge networks on aggregate growth and welfare. We develop a structural model in which a firm's productivity growth depends on its own innovation inputs as well as knowledge spillovers from other firms. Firms vary in innovation efficiency and occupy heterogeneous positions in knowledge networks. The model yields simple structural equations that characterize both the steady-state and transitional dynamics of the equilibrium. Using data on patent citations across Chinese manufacturing firms, we estimate the model's key parameters via a constrained simulated method of moments and assess its fit to the data. Simulations of our model are used to study (1) how firm-level instantaneous shocks propagate via inter-firm knowledge networks and translate into aggregate dynamic effects, (2) how governments should subsidize firm innovation in the presence of inter-firm knowledge spillovers, and (3) how inter-firm knowledge networks affect the productivity and welfare implications of trade liberalization.