A simple macroeconomic model with banking, financial frictions, and flexible exchange rates is used to study the performance of fiscal, monetary and macroprudential policy combinations in response to domestic and external shocks. After characterizing the transmission process of each instrument, a diagrammatic analysis of how these policies should be used, either individually or jointly, to promote economic and financial stability, is provided. The analysis shows that whether a policy should be assigned to internal or external balance, and whether it should be contractionary or expansionary, depends not only on the nature of the shocks impinging on the economy but also on the range of tools available to policymakers and the strength of financial frictions. In particular, in response to an external financial shock, monetary policy should be assigned to external balance, and fiscal policy or macroprudential regulation to internal balance. These two policies are substitutes when used in combination with monetary policy.

This paper studies the extent to which alternative loan loss provisioning regimes affect the procyclicality of the financial system and financial volatility. It uses a DSGE model with financial frictions (namely, collateral effects and economies of scope in banking) and a generic formulation of provisioning regimes. Numerical experiments with a parameterized version of the model show that cyclically adjusted (or, more commonly called, dynamic) provisioning can be highly effective in terms of mitigating procyclicality and financial risks, measured in terms of the volatility of the credit-output ratio and real house prices, in response to financial shocks. The optimal combination of simple cyclically adjusted provisioning and countercyclical reserve requirement rules is also studied. The simultaneous use of these instruments does not improve the ability of either one of them to mitigate financial volatility, making them (partial) substitutes rather than complements.