ISER Discussion Paper, Institute of Social and Economic Research, Osaka University 984
We construct a monopolistic competition model considering different markups across industries and firm-level heterogeneity of productivity. An excess entry occurs in low-markup (competitive) industry, and vice versa in high-markup (non-competitive) industry. To achieve the optimum allocation, a social planner should implement an appropriate mix of policies, whose requirement is tighter than the homogeneous-firm model under some situations. The total amount of optimum subsidy (tax) is dependent on the property of distribution when the elasticity of substitution between industries is above unity.
welfare optimum policy firm-level heterogeneity of productivity non-synchronization of markups Melitz-type model