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High interest rate currencies tend to appreciate. This is the uncovered interest rate parity (UIP) puzzle. It is primarily a statement about short-term interest rates and how they are related to exchange rates. Short-term interest rates are strongly affected by monetary policy. The UIP puzzle, therefore, can be restated in terms of monetary policy. Do foreign and domestic monetary policies imply exchange rates that violate UIP? We represent monetary policy as foreign and domestic Taylor rules. Foreign and domestic pricing kernels determine the relationship between these Taylor rules and exchange rates. We examine different specifications for the Taylor rule and ask which can resolve the UIP puzzle. We find evidence in favor of a particular asymmetry. If the foreign Taylor rule responds to exchange rate variation but the domestic Taylor rule does not, the model performs better. A calibrated version of our model is consistent with many empirical observations on real and nominal exchange rates, including Fama's negative correlation between interest rate differentials and currency depreciation rates.
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We investigate markets for defaultable sovereign debt in which even though there are many identical lenders and symmetric information (including no hidden actions), perfect competition does not obtain. When a private lender allows a sovereign country to increase its level of indebtedness, that lender implicitly imposes a default externality on others who have lent to that sovereign. That is, in the case where the borrower would be able to pay back the first loan in the absence of a second loan, the borrower may have a strong incentive to take both loans and default on both loans. When a lender has no control over the actions of other lenders, they must anticipate this behavior and devise a lending strategy that is consistent with the strategies not only of the sovereign borrower, but also of other lenders. We develop a model of this strategic lending behavior in the presence of default, and show that even though there are many competing lenders, the perfectly competitive outcome does not necessarily obtain. Moreover, the equilibrium can result in monopoly-like outcomes in prices and quantities. We also study the consequences of intervention in these markets by a seemingly benevolent international financial institution, and find that these interventions, though well-intentioned, can in some cases be welfare reducing for sovereign countries and welfare improving for private lenders.
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We provide a user's guide to exotic' preferences: nonlinear time aggregators, departures from expected utility, preferences over time with known and unknown probabilities, risk-sensitive and robust control, hyperbolic' discounting, and preferences over sets ( temptations'). We apply each to a number of classic problems in macroeconomics and finance, including consumption and saving, portfolio choice, asset pricing, and Pareto optimal allocations.
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We examine the relationship between monetary-policy-induced changes in short interest rates and yields on long-maturity default-free bonds. The volatility of the long end of the term structure and its relationship with monetary policy are puzzling from the perspective of simple structural macroeconomic models. We explore whether richer models of risk premiums, specifically stochastic volatility models combined with Epstein-Zin recursive utility, can account for such patterns. We study the properties of the yield curve when inflation is an exogenous process and compare this to the yield curve when inflation is endogenous and determined through an interest-rate/Taylor rule. When inflation is exogenous, it is difficult to match the shape of the historical average yield curve. Capturing its upward slope is especially difficult as the nominal pricing kernel with exogenous inflation does not exhibit any negative autocorrelation - a necessary condition for an upward sloping yield curve as shown in Backus and Zin (1994). Endogenizing inflation provides a substantially better fit of the historical yield curve as the Taylor rule provides additional flexibility in introducing negative autocorrelation into the nominal pricing kernel. Additionally, endogenous inflation provides for a flatter term structure of yield volatilities which better fits historical bond data.
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Long-run asset-pricing restrictions in a macro term-structure model identify discretionary monetary policy separately from a policy rule. We find that policy discretion is an important contributor to aggregate risk. In addition, discretionary easing coincides with good news about the macroeconomy in the form of lower inflation, higher output growth, and lower risk premiums on short-term nominal bonds. However, it also coincides with bad news about long-term financial conditions in the form of higher risk premiums on long-term nominal bonds. Shocks to the rule correlate with changes in the yield curve's level. Shocks to discretion correlate with changes in its slope.
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Mathematical models of bond pricing are used by both academics and Wall Street practitioners, with practitioners introducing time-dependent parameters to fit arbitrage-free models to selected asset prices. We show, in a simple one-factor setting, that the ability of such models to reproduce a subset of security prices need not extend to state-contingent claims more generally. The popular Black-Derman-Toy model, for example, overprices call options on long bonds relative to those on short bonds when interest rates exhibit mean reversion. We argue, more generally, that the additional parameters of arbitrage-free models should be complemented by close attention to fundamentals, which might include mean reversion, multiple factors, stochastic volatility, and/or non-normal interest rate distributions.
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We provide an axiomatic model of preferences over atemporal risks that generalizes Gul (1991) A Theory of Disappointment Aversion' by allowing risk aversion to be first order' at locations in the state space that do not correspond to certainty. Since the lotteries being valued by an agent in an asset-pricing context are not typically local to certainty, our generalization, when embedded in a dynamic recursive utility model, has important quantitative implications for financial markets. We show that the state-price process, or asset-pricing kernel, in a Lucas-tree economy in which the representative agent has generalized disappointment aversion preferences is consistent with the pricing kernel that resolves the equity-premium puzzle. We also demonstrate that a small amount of conditional heteroskedasticity in the endowment-growth process is necessary to generate these favorable results. In addition, we show that risk aversion in our model can be both state-dependent and counter-cyclical, which empirical research has demonstrated is necessary for explaining observed asset-pricing behavior.
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We inject aggregate uncertainty - risk and ambiguity - into an otherwise standard business cycle model and describe its consequences. We find that increases in uncertainty generally reduce consumption, but they do not account, in this model, for either the magnitude or the persistence of the most recent recession. We speculate about extensions that might do better along one or both dimensions.
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High interest rate currencies tend to appreciate. This is the uncovered interest rate parity (UIP) puzzle. It is primarily a statement about short-term interest rates and how they are related to exchange rates. Short-term interest rates are strongly affected by monetary policy. The UIP puzzle, therefore, can be restated in terms of monetary policy. Do foreign and domestic monetary policies imply exchange rates that violate UIP? We represent monetary policy as foreign and domestic Taylor rules. Foreign and domestic pricing kernels determine the relationship between these Taylor rules and exchange rates. We examine different specifications for the Taylor rule and ask which can resolve the UIP puzzle. We find evidence in favor of a particular asymmetry. If the foreign Taylor rule responds to exchange rate variation but the domestic Taylor rule does not, the model performs better. A calibrated version of our model is consistent with many empirical observations on real and nominal exchange rates, including Fama's negative correlation between interest rate differentials and currency depreciation rates.