Anatomizing Incomplete-Markets Small Open Economies: Policy Trade-Offs And Equilibrium Determinacy

We propose a simple incomplete-markets small-open-economy model that is amenable to analytical dissection of its policy-relevant mechanisms. In contrast to its complete-markets limit, the equilibrium real exchange rate is irreducible from the incomplete-markets equilibrium. Market incompleteness exacerbates the domestic-inflation and output-gap monetary-policy trade-off in two ways: its steepness and its resulting endogenous cost-push to the trade-off. The latter depends on an equilibrium combination of structural shocks and on agents' beliefs of future events. Thus, in comparison to its complete-markets and closed-economy limits, standard Taylor-type rules are less capable of inducing determinate rational expectations equilibrium in our environment. Despite the larger policy trade-off under incomplete markets, simple policies that also respond to exchange-rate growth are able to manage expectations that drive the endogenous cost-push term. However, policies that respond directly to expectations may turn out to exacerbate the cost-push trade-off further, and thus, to be more likely to fuel self-fulfilling multiple or unstable equilibria.