Over the past seven years, the DIG and DIGNAR models have complemented the IMF and World Bank debt sustainability framework (DSF) analysis, over 65 country applications. They have provided useful insights in the context of program and surveillance work, based on qualitative and quantitative...

We present an extensive analysis of the consequences for global equilibrium determinacy in flexible-price open economies of implementing active interest rate rules, i.e., monetary rules where the nominal interest rate responds more than proportionally to inflation. We show that conditions under...

We develop a tractable open-economy new-Keynesian model with two sectors to analyze the short-term effects of aid-financed fiscal expansions. We distinguish between spending the aid, which is under the control of the fiscal authorities, and absorbing the aid-using the aid to finance a higher...

Empirical evidence suggests that goods are highly heterogeneous with respect to the degree of price rigidity. We develop a DSGE model featuring heterogeneous nominal rigidities across two sectors to study the equilibrium determinacy and stability under adaptive learning for interest rate rules...

This paper presents the DIGNAR (Debt, Investment, Growth, and Natural Resources) model, which can be used to analyze the debt sustainability and macroeconomic effects of public investment plans in resource-abundant developing countries. DIGNAR is a dynamic, stochastic model of a small open...

We study the role of the exchange rate regime, reserve accumulation, and sterilization policies in the macroeconomics of aid surges. Absent sterilization, a peg allows for almost full aid absorption — an increase in the current account deficit net of aid—delivering the same effects as those...

The permanent income hypothesis implies that frictionless open economies with exhaustible natural resources should save abroad most of their resource windfalls and, therefore, feature current account surpluses. Resource-rich developing countries (RRDCs), on the other hand, face substantial...

We develop a model to study the macroeconomic effects of public investment surges in low-income countries, making explicit: (i) the investment-growth linkages; (ii) public external and domestic debt accumulation; (iii) the fiscal policy reactions necessary to ensure debt-sustainability; and (iv)...

This paper presents an analysis of the public investment scaling-up strategy for Togo using a dynamic macroeconomic model that explicitly analyzes the links between public investment, economic growth, and debt sustainability. In the model, public capital is productive and complementary to...