Monetary Policy in an Uncertain World: Probability Models and the Design of Robust Monetary Rules

NIPFP Working Paper 72
[PDF]

Paul Levine
July 2010

Abstract

The past forty years or so has seen a remarkable transformation in macro-models used by central banks, policymakers and forecasting bodies. This paper describes this transformation from reduced-form behavioural equations estimated separately, through contemporary micro-founded dynamic stochastic general equilibrium (DSGE) models estimated by systems methods. In particular by treating DSGE models estimated by Bayesian-Maximum-Likelihood methods I argue that they can be considered as probability models in the sense described by Sims (2007) and be used for risk-assessment and policy design. This is true for any one model, but with a range of models on offer it is also possible to design interest rate rules that are simple and robust across the rival models and across the distribution of parameter estimates for each of these rivals as in Levine et al. (2008). After making models better in a number of important dimensions, a possible road ahead is to consider rival models as being distinguished by the model of expectations. This would avoid becoming `a prisoner of a single system' at least with respect to expectations formation where, as I argue, there is relatively less consensus on the appropriate modelling strategy.

Understanding the ADR Premium under Market Segmentation

NIPFP Working Paper 71
[PDF]

Matthieu Stigler, Ajay Shah and Ila Patnaik
July 2010

Abstract

Capital controls can induce large and persistent deviations from the Law of One Price for cross-listed stocks in international capital markets. A considerable literature has explored firm-specific factors which influence ADR pricing when LOP is violated. In this paper, we examine the interlinkages between Indian ADR premiums and macro economic time-series. We construct an ADR premium index, whereby diversification across firms diminishes idiosyncratic fluctuations associated with each security. We find that the S&P 500 index and the domestic Nifty index influence the ADR Premium Index. Positive shocks to the ADR premium index precede higher purchases by foreign investors on the domestic market, and precede positive returns on the domestic index.

A Floating versus Managed Exchange Rate Regime in a DSGE Model of India

NIPFP Working Paper 70
[PDF]

Nicoletta Batini, Vasco Gabriel, Paul Levine and Joseph Pearlman
July 2010

Abstract

We first develop a two-bloc model of an emerging open economy interacting with the rest of the world calibrated using Indian and US data. The model features a financial accelerator and is suitable for examining the effects of financial stress on the real economy. Three variants of the model are highlighted with increasing degrees of financial frictions. The model is used to compare two monetary interest rate regimes: domestic Inflation targeting with a floating exchange rate (FLEX(D)) and a managed exchange rate (MEX). Both rules are characterized as a Taylor-type interest rate rules. MEX involves a nominal exchange rate target in the rule and a constraint on its volatility. We find that the imposition of a low exchange rate volatility is only achieved at a significant welfare loss if the policymaker is restricted to a simple domestic inflation plus exchange rate targeting rule. If on the other hand the policymaker can implement a complex optimal rule then an almost fixed exchange rate can be achieved at a relatively small welfare cost. This finding suggests that future research should examine alternative simple rules that mimic the fully optimal rule more closely.