A random coefficient model of speculative attacks: The case of the Mexican peso

A considerable body of theoretical and empirical literature has developed seeking to explain the timing, magnitude, and mechanics of speculative attacks against currencies. This paper extends the empirical specification of the traditional speculative attack model by developing a random coefficient (RC) model which, as we show, encompasses a variety of fixed-coefficient models as special cases. Two classes of models (fixed- and random-coefficient models) are estimated for the case of Mexican peso over the period January 1988 to Novemeber 1994, while forecasts of the peso/U.S. dollar exchange rate are generated for the period December 1994 through December 1995. The comparison of forecast errors generated by five model specifications indicates that forecasts based on the RC procedures are superior to those based on the fixed-coefficient estimation. It is also shown that there are good theoretical reasons why the RC procedure performs better in prediction than the fixed-coefficient procedure.     

THE COMPLEX RESPONSE OF MONETARY POLICY TO THE EXCHANGE RATE

We estimate a flexible non‐linear monetary policy rule for the United Kingdom to examine the response of policymakers to the real exchange rate. We have three main findings. First, policymakers respond to real exchange rate misalignment rather than to the real exchange rate itself. Second, policymakers ignore small deviations of the exchange rate; they only respond to real exchange under‐valuations of more than 4% and over‐valuations of more than 5%. Third, the response of policymakers to inflation is smaller when the exchange rate is over‐valued and larger when it is under‐valued. None of these responses is allowed for in the widely used linear Taylor‐type rules, suggesting that monetary policy is better analysed using a more sophisticated model, such as the one suggested in this paper.     

Asset price volatility in a nonconvex general equilibrium model

Summary. Asset prices and returns are known to vary significantly more than␣output or aggregate consumption growth, and an order of magnitude in excess of what is justified by innovations to fundamentals. We study excess price volatility in a lifecycle economy with two assets (claims on capital and␣a public debt bubble), heterogeneous agents, and increasing returns to financial intermediation. We show that a relatively modest nonconvexity generates a set valued equilibrium correspondence in asset prices, with two␣stable branches. Price volatility is the outcome of an equilibrium selection mechanism, which mixes adaptive learning with “noise”, and alternates stochastically between the two stable branches of the price correspondence. Received: March 19, 1998; revised version: June 2, 1998