A major puzzle in international finance is that high interest rate currencies tend to appreciate (forward discount puzzle). Motivated by the fact that only a small fraction of foreign currency holdings is actively managed, we calibrate a two-country model in which agents make infrequent portfolio decisions. We show that the model can account for the forward discount puzzle. It can also account for several related empirical phenomena, including that of “delayed overshooting.” We also show that making infrequent portfolio decisions is optimal as the welfare gain from active currency management is smaller than the corresponding fees.

Two well-known, but seemingly contradictory, features of exchange rates are that they are close to a random walk (RW) while at the same time exchange rate changes are predictable by interest rate di¤erentials. The RW hypothesis received strong support from the work of Richard A. Meese and Kenneth Rogo ¤ (1983) who were the …rst to show that macro models of exchange rate determination could not beat the RW in predicting exchange rates. On the other hand, Eugene F. Fama (1984) showed that high interest rate currencies tend to subsequently appreciate. This is known as the forward discount puzzle and stands in contrast to Uncovered Interest Parity (UIP), which says that a positive interest di¤erential should lead to an expected depreciation of equal magnitude. The RW hypothesis and the forward discount puzzle are not as contradictory as it seems since the predictability of exchange rate changes by interest di¤erentials is limited. For example, Fama (1984) reports an average R2 of 0.01 when regressing monthly exchange rate changes on beginning-of-period interest di¤erentials. Instead of opposing these two features of the data, in this paper we investigate whether in fact they may be related to each other.

Empirical evidence shows that most exchange rate volatility at short to medium horizons is related to order flow and not to macroeconomic variables. We introduce symmetric information dispersion about future macroeconomic fundamentals in a dynamic rational expectations model in order to explain these stylized facts. Consistent with the evidence, the model implies that (a) observed fundamentals account for little of exchange rate volatility in the short to medium run, (b) over long horizons, the exchange rate is closely related to observed fundamentals, (c) exchange rate changes are a weak predictor of future fundamentals, and (d) the exchange rate is closely related to order flow.

While empirical evidence finds only a weak relationship between nominal exchange rates and macroeconomic fundamentals, forex markets participants often attribute exchange rate movements to a macroeconomic variable. The variables that matter, however, appear to change over time and some variable is typically taken as a scapegoat. For example, the current dollar weakness appears to be caused almost exclusively by the large current account deficit, while its previous strength was explained mainly by growth differentials. In this paper, we propose an explanation of this phenomenon in a simple monetary model of the exchange rate with noisy rational expectations, where investors have heterogeneous information on some structural parameter of the economy. In this context, there may be rational confusion about the true source of exchange rate fluctuations, so that if an unobservable variable affects the exchange rate, investors may attribute this movement to some current macroeconomic fundamental. We show that this effect applies only to variables with large imbalances. The model thus implies that the impact of macroeconomic variables on the exchange rate changes over time.

This paper develops a simple general-equilibrium framework to study the effect of the exchange-rate system on trade and welfare. An important feature of the model is deviations from purchasing-power parity, caused by rigid price setting in buyers' currency. In a benchmark model with separable preferences and only monetary shocks, trade is unaffected by the exchange-rate system, consistent with most evidence. In general, both trade and welfare can be higher under either exchange-rate system, depending on preferences and on the monetary-policy rules followed under each system. There is no one-to-one relationship between the levels of trade and welfare across exchange-rate systems.

Using data on international equity portfolio allocations by U.S. mutual funds, we estimate a portfolio expression derived from a standard mean-variance portfolio model extended with portfolio frictions. The optimal portfolio depends on the previous month and the buy-and-hold portfolio shares, and a present discounted value of expected excess returns. We estimate expected return differentials and use them in the portfolio regressions. The estimates imply significant portfolio frictions and a modest rate of risk aversion. While mutual fund portfolios significantly respond to expected returns, portfolio frictions lead to a weaker and a more gradual portfolio response to changes in expected returns.

We introduce a portfolio friction in a two-country DSGE model where investors face a constant probability to make new portfolio decisions. The friction leads to a more gradual portfolio adjustment to shocks and a weaker portfolio response to changes in expected excess returns. We apply the model to monthly data for the US and the rest of the world for equity portfolios. We show that the model is consistent with a broad set of evidence related to portfolios, equity prices, and excess returns for an intermediate level of friction. The evidence includes portfolio inertia, limited sensitivity to expected excess returns, a significant impact of financial shocks, excess return predictability, and asset price momentum and reversal.

Recent crises have seen large spikes in asset price risk. We propose an explanation for such panics based on self-fulfilling shifts in beliefs about risk. A negative link between the current level and the future risk of an asset price leads to a circular relationship between the stochastic process of asset price risk and the price itself. Self-fulfilling shifts in perceived risk can be coordinated around a pure sunspot or around a macro fundamental. In a risk panic, a macro fundamental can be a focal point that affects both the magnitude of the panic and subsequent shifts in perceived risk.

There has been a long debate about whether speculators are stabilizing or not. We consider a model where speculators have a stabilizing role in normal times, but may also provoke large risk panics. The very feature that makes arbitrageurs liquidity providers in normal times, namely their tolerance of risk, enables a large increase in asset price risk during a financial panic. We show that a policy that discourages balance sheet risk reduces the magnitude of financial panics, as well as asset price risk in both normal and panic states.

We examine the welfare-based opportunity cost of foreign exchange (FX) intervention when both covered interest rate parity (CIP) and uncovered interest rate parity (UIP) deviations are present. We consider a small open economy that receives international capital flows through constrained international financial intermediaries. Deviations from CIP come from limited arbitrage or through a convenience yield, while UIP deviations are also affected by global risk. We show that the sign of CIP and UIP deviations may differ for safe haven countries. We find that FX reserves may provide a net benefit, rather than a cost, when international intermediaries value the safe-haven properties of a currency more than domestic households. We show that this has been the case for the Swiss franc and the Japanese Yen. We examine the optimal policy of a constrained central bank planner in this context.