Market Structure and Fiscal Policy Effectiveness

In a monopolistic competition macromodel with endogenous market structure, the fiscal multiplier is shown to consist of two components. The first depicts the response of output to a fiscal expansion through the conventional channels that disregard the role of market imperfections. The second component captures the effects of firms' market power as well as the policy‐induced change in market structure. The latter effect—which has not been taken into account in existing studies—is shown to be quite significant in raising the fiscal multiplier (even above unity) and in improving consumers' welfare when the labour market is competitive.