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The Taylor Rule and Interval Forecast For Exchange Rates1

Jian Wang2 and Jason J. Wu3

NOTE: International Finance Discussion Papers are preliminary materials circulated to stimulate discussion and critical comment. References in publications to International Finance Discussion Papers (other than an acknowledgment that the writer has had access to unpublished material) should be cleared with the author or authors. Recent IFDPs are available on the Web at http://www.federalreserve.gov/pubs/ifdp/. This paper can be downloaded without charge from the Social Science Research Network electronic library at http://www.ssrn.com/.


Abstract:

This paper attacks the Meese-Rogoff puzzle from a different perspective: out-of-sample interval forecasting. Most studies in the literature focus on point forecasts. In this paper, we apply Robust Semiparametric (RS) interval forecasting to a group of Taylor rule models. Forecast intervals for twelve OECD exchange rates are generated and modified tests of Giacomini and White (2006) are conducted to compare the performance of Taylor rule models and the random walk. Our contribution is twofold. First, we find that in general, Taylor rule models generate tighter forecast intervals than the random walk, given that their intervals cover out-of-sample exchange rate realizations equally well. This result is more pronounced at longer horizons. Our results suggest a connection between exchange rates and economic fundamentals: economic variables contain information useful in forecasting the distributions of exchange rates. The benchmark Taylor rule model is also found to perform better than the monetary and PPP models. Second, the inference framework proposed in this paper for forecast-interval evaluation can be applied in a broader context, such as inflation forecasting, not just to the models and interval forecasting methods used in this paper.

Keywords: The exchange rate disconnect puzzle, exchange rate forecast, interval forecasting

JEL classification: F31, C14, C53



1.  Introduction

Recent studies explore the role of monetary policy rules, such as Taylor rules, in exchange rate determination. They find empirical support in these models for the linkage between exchange rates and economic fundamentals. Our paper extends this literature from a different perspective: interval forecasting. We find that the Taylor rule models can outperform the random walk, especially at long horizons, in forecasting twelve OECD exchange rates based on relevant out-of-sample interval forecasting criteria. The benchmark Taylor rule model is also found to perform relatively better than the standard monetary model and the purchasing power parity (PPP) model.

In a seminal paper, Meese and Rogoff (1983) find that economic fundamentals - such as the money supply, trade balance and national income - are of little use in forecasting exchange rates. They show that existing models cannot forecast exchange rates better than the random walk in terms of out-of-sample forecasting accuracy. This finding suggests that exchange rates may be determined by something purely random rather than economic fundamentals. Meese and Rogoff's (1983) finding has been named the Meese-Rogoff puzzle in the literature.

In defending fundamental-based exchange rate models, various combinations of economic variables and econometric methods have been used in attempts to overturn Meese and Rogoff's finding. For instance, Mark (1995) finds greater exchange rate predictability at longer horizons.4 Groen (2000) and Mark and Sul (2001) detect exchange rate predictability by using panel data. Kilian and Taylor (2003) find that exchange rates can be predicted from economic models at horizons of 2 to 3 years, after taking into account the possibility of nonlinear exchange rate dynamics. Faust, Rogers, and Wright (2003) find that the economic models consistently perform better using real-time data than revised data, though they do not perform better than the random walk.

Recently, there is a growing strand of literature that uses Taylor rules to model exchange rate determination. Engel and West (2005) derive the exchange rate as a present-value asset price from a Taylor rule model. They also find a positive correlation between the model-based exchange rate and the actual real exchange rate between the US dollar and the Deutschmark (Engel and West, 2006). Mark (2007) examines the role of Taylor-rule fundamentals for exchange rate determination in a model with learning. In his model, agents use least-square learning rules to acquire information about the numerical values of the model's coefficients. He finds that the model is able to capture six major swings of the real Deutschmark-Dollar exchange rate from 1973 to 2005. Molodtsova and Papell (2009) find significant short-term out-of-sample predictability of exchange rates with Taylor-rule fundamentals for 11 out of 12 currencies vis-á-vis the U.S. dollar over the post-Bretton Woods period. Molodtsova, Nikolsko-Rzhevskyy, and Papell (2008a, 2008b) find evidence of out-of-sample predictability for the dollar/mark nominal exchange rate with forecasts based on Taylor rule fundamentals using real-time data, but not revised data. Chinn (forthcoming) also finds that Taylor rule fundamentals do better than other models at the one year horizon. With a present-value asset pricing model as discussed in Engel and West (2005), Chen and Tsang (2009) find that information contained in the cross-country yield curves are useful in predicting exchange rates.

Our paper joins the above literature of Taylor-rule exchange rate models. However, we address the Meese and Rogoff puzzle from a different perspective: interval forecasting. A forecast interval captures a range in which the exchange rate may lie with a certain probability, given a set of predictors available at the time of forecast. Our contribution to the literature is twofold. First, we find that for twelve OECD exchange rates, the Taylor rule models in general generate tighter forecast intervals than the random walk, given that their intervals cover the realized exchange rates (statistically) equally well. This finding suggests an intuitive connection between exchange rates and economic fundamentals beyond point forecasting: the use of economic variables as predictors helps narrow down the range in which future exchange rates may lie, compared to random walk forecast intervals. Second, we propose an inference framework for cross-model comparison of out-of-sample forecast intervals. The proposed framework can be used for forecast-interval evaluation in a broader context, not just for the models and methods used in this paper. For instance, the framework can also be used to evaluate out-of-sample inflation forecasting.

As we will discuss later, we in fact derive forecast intervals from estimates of the distribution of changes in the exchange rate. Hence, in principle, evaluations across models can be done based on distributions instead of forecast intervals. However, focusing on interval forecasting performance allows us to compare models in two dimensions that are more relevant to practitioners: empirical coverage and length.

While the literature on interval forecasting for exchange rates is sparse, several authors have studied out-of-sample exchange rate density (distribution) forecasts, from which interval forecasts can be derived. Diebold, Hahn and Tay (1999) use the RiskMetrics model of JP Morgan (1996) to compute half-hour-ahead density forecasts for Deutschmark/Dollar and Yen/Dollar returns. Christoffersen and Mazzotta (2005) provide option-implied density and interval forecasts for four major exchange rates. Boero and Marrocu (2004) obtain one-day-ahead density forecasts for the Euro nominal effective exchange rate using self-exciting threshold autoregressive (SETAR) models. Sarno and Valente (2005) evaluate the exchange rate density forecasting performance of the Markov-switching vector equilibrium correction model that is developed by Clarida, Sarno, Taylor and Valente (2003). They find that information from the term structure of forward premia help the model to outperform the random walk in forecasting out-of-sample densities of the spot exchange rate. More recently, Hong, Li, and Zhao (2007) construct half-hour-ahead density forecasts for Euro/Dollar and Yen/Dollar exchange rates using a comprehensive set of univariate time series models that capture fat tails, time-varying volatility and regime switches.

There are several common features across the studies listed above, which make them different from our paper. First, the focus of the above studies is not to make connections between the exchange rate and economic fundamentals. These studies use high frequency data, which are not available for most conventional economic fundamentals. For instance, Diebold, Hahn, and Tay (1999) and Hong, Li, and Zhao (2007) use intra-day data. With the exception of Sarno and Valente (2005), all the studies focus only on univariate time series models. Second, these studies do not consider multi-horizon-ahead forecasts, perhaps due to the fact that their models are often highly nonlinear. Iterating nonlinear density models multiple horizons ahead is analytically difficult, if not infeasible. Lastly, the above studies assume that the densities are analytically defined for a given model. The semiparametric method used in this paper does not impose such restrictions.

Our choice of the semiparametric method is motivated by the difficulty of using macroeconomic models in exchange rate interval forecasting: these models typically do not describe the future distributions of exchange rates. For instance, the Taylor rule models considered in this paper do not describe any features of the data beyond the conditional means of future exchange rates. We address this difficulty by applying Robust Semiparametric forecast intervals (hereon RS forecast intervals) of Wu (2009).5 This method is useful since it does not require the model be correctly specified, or contain parametric assumptions about the future distribution of exchange rates.

We apply RS forecast intervals to a set of Taylor rule models that differ in terms of the assumptions on policy and interest rate smoothing rules. Following Molodtsova and Papell (2009), we include twelve OECD exchange rates (relative to the US dollar) over the post-Bretton Woods period in our dataset. For these twelve exchange rates, the out-of-sample RS forecast intervals at different forecast horizons are generated from the Taylor rule models and then compared with those of the random walk. The empirical coverages and lengths of forecast intervals are used as the evaluation criteria. Our empirical coverage and length tests are modified from Giacomini and White's (2006) predictive accuracy tests in the case of rolling, but fixed-size, estimation samples.

For a given nominal coverage (probability), the empirical coverage of forecast intervals derived from a forecasting model is the probability that the out-of-sample realizations (exchange rates) lie in the intervals. The length of the intervals is a measure of its tightness: the distance between its upper and lower bound. In general, the empirical coverage is not the same as its nominal coverage. Significantly missing the nominal coverage indicates poor quality of the model and intervals. One certainly wants the forecast intervals to contain out-of-sample realizations as close as possible to the probability they target. Most evaluation methods in the literature focus on comparing empirical coverages across models, following the seminal work of Christoffersen (1998). Following this literature, we first test whether forecast intervals of the Taylor rule models and the random walk have equally accurate empirical coverages. The model with more accurate coverages is considered the better model. In the cases where equal coverage accuracy cannot be rejected, we further test whether the lengths of forecast intervals are the same. The model with tighter forecast intervals provides more useful information about future values of the data, and hence is considered as a more useful forecasting model.

It is also important to establish what this paper is not attempting. First, the inference procedure does not carry the purpose of finding the correct model specification. Rather, inference is on how useful models are in generating forecast intervals, measured in terms of empirical coverages and lengths. Second, this paper does not consider the possibility that there might be alternatives to RS forecast intervals for the exchange rate models we consider. Some models might perform better if parametric distribution assumptions (e.g. the forecast errors are conditionally heteroskedastic and $ t-$distributed) or other assumptions (e.g. the forecast errors are independent of the predictors) are added. One could presumably estimate the forecast intervals differently based on the same models, and then compare those with the RS forecast intervals, but this is out of the scope of this paper. As we described, we choose the RS method for the robustness and flexibility achieved by the semiparametric approach.

First, the models considered in this paper are standard macroeconomic models for exchange rate determination. These models do not contain theory about the underlying distributions. Using RS forecast intervals allows us to refrain from having to impose subjective additional structures on the models. Our goal is to use existing models to generate forecast intervals, instead of developing new models. Second, RS forecast intervals are good candidates as they always consistently estimates their population counterparts, independent of the properties of the models and error terms ( $ \varepsilon_{m,\tau+h}$). With the sample sizes we have, RS forecast intervals are deemed good approximations to the truth.

Our benchmark Taylor rule model is from Engel and West (2005) and Engel, Wang, and Wu (2008). For the purpose of comparison, several alternative Taylor rule models are also considered. These setups have been studied by Molodtsova and Papell (2009) and Engel, Mark, and West (2007). In general, we find that the Taylor rule models perform better than the random walk model, especially at long horizons: the models either have more accurate empirical coverages than the random walk, or in cases of equal coverage accuracy, the models have tighter forecast intervals than the random walk. The evidence of exchange rate predictability is much weaker in coverage tests than in length tests. In most cases, the Taylor rule models and the random walk have statistically equally accurate empirical coverages. So, under the conventional coverage test, the random walk model and the Taylor rule models perform equally well. However, the results of length tests suggest that Taylor rule fundamentals are useful in generating tighter forecasts intervals without losing accuracy in empirical coverages.

We also consider two other popular models in the literature: the monetary model and the model of purchasing power parity (PPP). Based on the same criteria, both models are found to perform better than the random walk in interval forecasting. As with the Taylor rule models, most evidence of exchange rate predictability comes from the length test: economic models have tighter forecast intervals than the random walk given statistically equivalent coverage accuracy. The PPP model performs worse than the benchmark Taylor rule model and the monetary model at short horizons. The benchmark Taylor rule model performs slightly better than the monetary model at most horizons.

Our findings suggest that exchange rate movements are linked to economic fundamentals. However, we acknowledge that the Meese-Rogoff puzzle remains difficult to understand. Although Taylor rule models offer statistically significant length reductions over the random walk, the reduction of length is quantitatively small, especially at short horizons. Forecasting exchange rates remains a difficult task in practice. There are some impressive advances in the literature, but most empirical findings remain fragile. As mentioned in Cheung, Chinn, and Pascual (2005), forecasts from economic fundamentals may work well for some currencies during certain sample periods but not for other currencies or sample periods. Engel, Mark, and West (2007) recently show that a relatively robust finding is that exchange rates are more predictable at longer horizons, especially when using panel data. We find greater predictability at longer horizons in our exercise. It would be of interest to investigate connections between our findings and theirs.

Several recent studies have attacked the puzzle from a different angle: there are reasons that economic fundamentals cannot forecast the exchange rate, even if the exchange rate is determined by these fundamentals. Engel and West (2005) show that existing exchange rate models can be written in a present-value asset-pricing format. In these models, exchange rates are determined not only by current fundamentals but also by expectations of what the fundamentals will be in the future. When the discount factor is large (close to one), current fundamentals receive very little weight in determining the exchange rate. Not surprisingly, the fundamentals are not very useful in forecasting. Nason and Rogers (2008) generalize the Engel-West theorem to a class of open-economy dynamic stochastic general equilibrium (DSGE) models. Other factors such as parameter instability and mis-specification (for instance, Rossi 2005) may also play important roles in understanding the puzzle. It is interesting to investigate conditions under which we can reconcile our findings with these studies.

The remainder of this paper is organized as follows. Section two describes the forecasting models we use, as well as the data. In section three, we illustrate how the RS forecast intervals are constructed from a given model. We also propose loss criteria to evaluate the quality of the forecast intervals and test statistics that are based on Giacomini and White (2006). Section four presents results of out-of-sample forecast evaluation. Finally, section five contains concluding remarks.


2.  Models and Data

Seven models are considered in this paper. Let $ m=1,2,...,7$ be the index of these models and the first model be the benchmark model. A general setup of the models takes the form of:

$\displaystyle s_{t+h}-s_{t}=\alpha_{m,h}+\beta^{\prime}_{m,h}\mathbf{X}_{m,t}+\varepsilon _{m,t+h},$ (1)

where $ s_{t+h}-s_{t}$ is $ h$-period changes of the (log) exchange rate, and $ \mathbf{X}_{m,t}$ contains economic variables that are used in model $ m$. Following the literature of long-horizon regressions, both short- and long-horizon forecasts are considered. Models differ in economic variables that are included in matrix $ \mathbf{X}_{m,t}$. In the benchmark model,

$\displaystyle \mathbf{X}_{1,t}\equiv\left[ \begin{array}[c]{ccc} \pi_{t}-\pi_{t}^{\ast} & y_{t}^{gap}-y_{t}^{gap\ast} & q_{t}\\ & & \end{array} \right] ,$

where $ \pi_{t}$ ( $ \pi_{t}^{\ast}$) is the inflation rate, and $ y_{t}^{gap}$ ( $ y_{t}^{gap\ast}$) is the output gap in the home (foreign) country. The real exchange rate $ q_{t}$ is defined as $ q_{t}\equiv s_{t}+p_{t}^{\ast}-p_{t}$, where $ p_{t}$ ( $ p_{t}^{\ast}$) is the (log) consumer price index in the home (foreign) country. This setup is motivated by the Taylor rule model in Engel and West (2005) and Engel, Wang, and Wu (2008). The next subsection describes this benchmark Taylor rule model in detail.

We also consider the following models that have been studied in the literature:

Model 2: \begin{displaymath}\mathbf{X}_{2,t}\equiv\left[ \begin{array}[c]{cc} \pi_{t}-\pi_{t}^{\ast} & y_{t}^{gap}-y_{t}^{gap\ast}\ & \end{array}\right] \end{displaymath}
Model 3: \begin{displaymath}\mathbf{X}_{3,t}\equiv\left[ \begin{array}[c]{ccc} \pi_{t}-\pi_{t}^{\ast} & y_{t}^{gap}-y_{t}^{gap\ast} & i_{t-1}-i_{t-1}^{\ast }\ & & \end{array}\right] \end{displaymath},
  where $ i_{t}$ ( $ i_{t}^{\ast}$) is the short-term interest rate in the home (foreign) country.
Model 4: \begin{displaymath}\mathbf{X}_{4,t}\equiv\left[ \begin{array}[c]{cccc} \pi_{t}-\pi_{t}^{\ast} & y_{t}^{gap}-y_{t}^{gap\ast} & q_{t} & i_{t-1} -i_{t-1}^{\ast}\ & & & \end{array}\right] \end{displaymath}
Model 5: $ \mathbf{X}_{5,t}\equiv q_{t}$
Model 6: \begin{displaymath}\mathbf{X}_{6,t}\equiv\left[ \begin{array}[c]{c} s_{t}-\left[ (m_{t}-m_{t}^{\ast})-(y_{t}-y_{t}^{\ast})\right] \ \end{array}\right] \end{displaymath} ,
  where $ m_{t}$ ( $ m_{t}^{\ast}$) is the money supply and $ y_{t}$ ( $ y_{t}^{\ast}$) is total output in the home (foreign) country.
Model 7: $ \mathbf{X}_{7,t}\equiv0$

Models 2-4 are the Taylor rule models studied in Molodtsova and Papell (2009). Model 2 can be considered as the constrained benchmark model in which PPP always holds. Molodtsova and Papell (2009) include interest rate lags in models 3 and 4 to take into account potential interest rate smoothing rules of the central bank.6 Model 5 is the purchasing power parity (PPP) model and model 6 is the monetary model. Both models have been widely used in the literature. See Molodtsova and Papell (2009) for the PPP model and Mark (1995) for the monetary model. Model 7 is the driftless random walk model ( $ \alpha _{7,h}\equiv0$).7 Given a date $ \tau$ and horizon $ h$, the objective is to estimate the forecast distribution of $ s_{\tau+h}-s_{\tau}$ conditional on $ \mathbf{X}_{m,\tau}$, and subsequently build forecast intervals from the estimated forecast distribution. Before moving to the econometric method, we first describe the Taylor rule model that motivates the setup of our benchmark model.

2.1  Benchmark Taylor Rule Model

Our benchmark model is the Taylor rule model that is derived in Engel and West (2005) and Engel, Wang, and Wu (2008). Following Molodtsova and Papell (2009), we focus on models that depend only on current levels of inflation and the output gap.8 The Taylor rule in the home country takes the form of:

$\displaystyle \bar{i}_{t}=\bar{i}+\delta_{\pi}(\pi_{t}-\bar{\pi})+\delta_{y}y_{t} ^{gap}+u_{t},$ (2)

where $ \bar{i}_{t}$ is the central bank's target for the short-term interest rate at time $ t$, $ \bar{i}$ is the equilibrium long-term rate, $ \pi_{t}$ is the inflation rate, $ \bar{\pi}$ is the target inflation rate, and $ y_{t} ^{gap}$ is the output gap. The foreign country is assumed to follow a similar Taylor rule. In addition, we follow Engel and West (2005) to assume that the foreign country targets the exchange rate in its Taylor rule:

$\displaystyle \bar{i}_{t}^{\ast}=\bar{i}+\delta_{\pi}(\pi_{t}^{\ast}-\bar{\pi})+\delta _{y}y_{t}^{gap\ast}+\delta_{s}(s_{t}-\bar{s}_{t})+u_{t}^{\ast} ,$ (3)

where $ \bar{s}_{t}$ is the targeted exchange rate. Assume that the foreign country targets the PPP level of the exchange rate: $ \bar{s}_{t}=p_{t} -p_{t}^{\ast}$, where $ p_{t}$ and $ p_{t}^{\ast}$ are logarithms of home and foreign aggregate prices. In equation (3), we assume that the policy parameters take the same values in the home and foreign countries. Molodtsova and Papell (2009) denote this case as "homogeneous Taylor rules". Our empirical results also hold in the case of heterogenous Taylor rules. To simplify our presentation, we assume that the home and foreign countries have the same long-term inflation and interest rates. Such restrictions have been relaxed in our econometric model after we include a constant term in estimations.

We do not consider interest rate smoothing in our benchmark model. That is, the actual interest rate ($ i_{t}$) is identical to the target rate in the benchmark model:

$\displaystyle i_{t}=\bar{i}_{t}.$ (4)

Molodtsova and Papell (2009) consider the following interest rate smoothing rule:

$\displaystyle i_{t}=(1-\rho)\bar{i}_{t}+\rho i_{t-1}+\nu_{t},$ (5)

where $ \rho$ is the interest rate smoothing parameter. We include these setups in models 3 and 4. Note that our estimation methods do not require the monetary policy shock $ u_{t}$ and the interest rate smoothing shock $ \nu_{t}$ to satisfy any assumptions, aside from smoothness of their distributions when conditioned on predictors.

Substituting the difference of equations (2) and (3) into Uncovered Interest-rate Parity (UIP), we have:

$\displaystyle s_{t}=E_{t}\left\{ (1-b)\sum_{j=0}^{\infty }b^{j}(p_{t+j}-p^{*}_{t+j})-b\sum_{j=0}^{\infty}b^{j}\left[ \delta_{y} (y^{gap}_{t+j}-y_{t+j}^{gap\ast})+\delta_{\pi}(\pi_{t+j}-\pi^{*}_{t+j})\right] \right\} ,$ (6)

where the discount factor $ b=\frac{1}{1+\delta_{s}}$. Under some conditions, the present value asset pricing format in equation (6) can be written into an error-correction form:9

$\displaystyle s_{t+h}-s_{t}=\alpha_{h}+\beta _{h}z_{t}+\varepsilon_{t+h},$ (7)

where the deviation of the exchange rate from its equilibrium level is defined as:

$\displaystyle z_{t}=s_{t}-p_{t}+p_{t}^{\ast}+\frac{b}{1-b}\left[ \delta_{y}(y_{t}^{gap}-y_{t}^{gap\ast})+\delta_{\pi}(\pi_{t}-\pi_{t}^{\ast })\right] .$ (8)

We use equation (7) as our benchmark setup in calculating h-horizon-ahead out-of-sample forecasting intervals. According to equation (8), the matrix $ \mathbf{X} _{1,t}$ in equation (1) includes economic variables $ q_{t}\equiv s_{t}+p_{t}^{\ast}-p_{t}$, $ y_{t}^{gap}-y_{t}^{gap\ast}$, and $ \pi_{t}-\pi_{t}^{\ast}$.10

2.2  Data

The forecasting models and the corresponding forecast intervals are estimated using monthly data for twelve OECD countries. The United States is treated as the foreign country in all cases. For each country we synchronize the beginning and end dates of the data across all models estimated. The twelve countries and periods considered are: Australia (73:03-06:6), Canada (75:01-06:6), Denmark (73:03-06:6), France (77:12-98:12), Germany (73:03-98:12), Italy (74:12-98:12), Japan (73:03-06:6), Netherlands (73:03-98:12), Portugal (83:01-98:12), Sweden (73:03-04:11), Switzerland (75:09-06:6), and the United Kingdom (73:03-06:4).

The data is taken from Molodtsova and Papell (2009).11 With the exception of interest rates, the data is transformed by taking natural logs and then multiplying by 100. The nominal exchange rates are end-of-month rates taken from the Federal Reserve Bank of St. Louis database. Output data ($ y_{t}$) are proxied by Industrial Production (IP) from the International Financial Statistics (IFS) database. IP data for Australia and Switzerland are only available at a quarterly frequency, and hence are transformed from quarterly to monthly observations using the quadratic-match average option in Eviews 4.0 by Molodtsova and Papell (2009). Following Engel and West (2006), the output gap ( $ y_{t}^{gap}$) is calculated by quadratically de-trending the industrial production for each country.

Prices data ($ p_{t}$) are proxied by Consumer Price Index (CPI) from the IFS database. Again, CPI for Australia is only available at a quarterly frequency and the quadratic-match average is used to impute monthly observations. Inflation rates are calculated by taking the first differences of the logs of CPIs. The money market rate from IFS (or "call money rate") is used as a measure of the short-term interest rate set by the central bank. Finally, M1 is used to measure the money supply for most countries. M0 for the UK and M2 for Italy and Netherlands is used due to the unavailability of M1 data.


3.  Econometric Method

For a given model $ m$, the objective is to estimate from equation (1) the distribution of $ s_{\tau +h}-s_{\tau}$ conditional on data $ \mathbf{X}_{m,\tau}$ that is observed up to time $ \tau$. This is the $ h$-horizon-ahead forecast distribution of the exchange rate, from which the corresponding forecast interval can be derived. For a given $ \alpha$, the forecast interval of coverage $ \alpha \in(0,1)$ is an interval in which $ s_{\tau+h}-s_{\tau}$ is supposed to lie with a probability of $ \alpha$.

Models $ m=1,...,7$ in equation (1) provide only point forecasts of $ s_{\tau+h}-s_{\tau}$. In order to construct forecast intervals for a given model, we apply robust semiparametric (RS) forecast intervals to all models. The nominal $ \alpha$-coverage forecast interval of $ s_{\tau +h}-s_{\tau}$ conditional on $ \mathbf{X}_{m,\tau}$ can be obtained by the following three-step procedure:

Step 1.
Estimate model $ m$ by OLS and obtain residuals $ \widehat{\varepsilon}_{m,t+h}\equiv s_{t+h}-s_{t}-\widehat{\alpha} _{m,h}+\widehat{\beta}^{^{\prime}}_{m,h}\mathbf{X}_{m,t}$ , for $ t=1,...,\tau -h$.
Step 2.
For a range of values of $ \varepsilon$ (sorted residuals $ \{\widehat{\varepsilon}_{m,t+h}\}_{t=1}^{\tau-h}$), estimate the conditional distribution of $ \varepsilon_{m,\tau+h}\vert\mathbf{X}_{m,\tau}$ by:
$\displaystyle \widehat{P}(\varepsilon_{m,\tau+h}\le\varepsilon\vert\mathbf{X}_{m,\tau} )\equiv\frac{\sum_{t=1}^{\tau-h}1(\widehat{\varepsilon}_{m,t+h}\le\varepsilon) \mathbf{K}_{b}(\mathbf{X}_{m,t}-\mathbf{X}_{m,\tau})}{\sum_{t=1}^{\tau -h}\mathbf{K}_{b}(\mathbf{X}_{m,t}-\mathbf{X}_{m,\tau})},$ (9)

where $ \mathbf{K}_{b}(\mathbf{X}_{m,t}-\mathbf{X}_{m,\tau})\equiv b^{-d}\mathbf{K}((\mathbf{X}_{m,t}-\mathbf{X}_{m,\tau})/b)$ , $ \mathbf{K} (\cdot)$ is a multivariate Gaussian kernel with a dimension the same as that of $ \mathbf{X}_{m,t}$, and $ b$ is the smoothing parameter or bandwidth.12

Step 3.
Find the $ (1-\alpha)/2$ and $ (1+\alpha)/2$ quantiles of the estimated distribution, which are denoted by $ \widehat{\varepsilon }_{m,h}^{(1-\alpha)/2}$ and $ \widehat{\varepsilon}_{m,h}^{(1+\alpha)/2}$, repectively. The estimate of the $ \alpha$-coverage forecast interval for $ s_{\tau+h}-s_{\tau}$ conditional on $ \mathbf{X}_{m,\tau}$ is:
$\displaystyle \widehat{I}^{\alpha}_{m,\tau+h}\equiv(\widehat{\beta}_{m,h}^{\prime} \mathbf{X}_{m,\tau}+\widehat{\varepsilon}_{m,h}^{(1-\alpha)/2}, \widehat {\beta}_{m,h}^{\prime}\mathbf{X}_{m,\tau}+\widehat{\varepsilon}_{m,h} ^{(1+\alpha)/2})$ (10)

For each model $ m$, the above method uses the forecast models in equation (1) to estimate the location of the forecast distribution, while the nonparametric kernel distribution estimate is used to estimate the shape. As a result, the interval obtained from this method is semiparametric. Wu (2009) shows that under some weak regularity conditions, this method consistently estimates the forecast distribution,13 and hence the forecast intervals of $ s_{\tau+h}-s_{\tau}$ conditional on $ \mathbf{X} _{m,\tau}$, regardless of the quality of model $ m$. That is, the forecast intervals are robust. Stationarity of economic variables is one of those regularity conditions. In our models, exchange rate differences, interest rates and inflation rates are well-known to be stationary, while empirical tests for real exchange rates and output gaps generate mixed results. These results may be driven by the difficulty of distinguishing a stationary, but persistent, variable from a non-stationary one. In this paper, we take the stationarity of these variables as given.

Model 7 is the random walk model. The estimator in equation (9) becomes the Empirical Distribution Function (EDF) of the exchange rate innovations. Under regularity conditions, equation (9) consistently estimates the unconditional distribution of $ s_{\tau+h}-s_{\tau}$, and can be used to form forecast intervals for $ s_{\tau+h}$. The forecast intervals of economic models and the random walk are compared. Our interest is to test whether RS forecast intervals based on economic models are more accurate than those based on the random walk model. We focus on the empirical coverage and the length of forecast intervals in our tests.

Following Christoffersen (1998) and related work, the first standard we use is the empirical coverage. The empirical coverage should be as close as possible to the nominal coverage ($ \alpha$). Significantly missing the nominal coverage indicates the inadequacy of the model and predictors for the given sample size. For instance, if 90% forecast intervals calculated from a model contain only 50% of out-of-sample observations, the model can hardly be identified as useful for interval forecasting. This case is called under-coverage. In contrast, over-coverage implies that the intervals could be reduced in length (or improved in tightness), but the forecast interval method and model are unable to do that for the given sample size. An economic model is said to outperform the random walk if its empirical coverage is more accurate than that of the random walk.

On the other hand, the empirical coverage of an economic model may be equally accurate as that of the random walk model, but the economic model has tighter forecast intervals than the random walk. We argue that the lengths of forecast intervals signify the informativeness of the intervals given that these intervals have equally accurate empirical coverages. In this case, the economic model is also considered to outperform the random walk in forecasting exchange rates. The empirical coverage and length tests are conducted at both short and long horizons for the six economic models relative to the random walk for each of the twelve OECD exchange rates.

We use tests that are applications of the unconditional predictive accuracy inference framework of Giacomini and White (2006). Unlike the tests of Diebold and Mariano (1995) and West (1996), our forecast evaluation tests do not focus on the asymptotic features of the forecasts. Rather, in the spirit of Giacomini and White (2006), we are comparing the population features of forecasts generated by rolling samples of fixed sample size. This contrasts to the traditional forecast evaluation methods in that although it uses asymptotic approximations to do the testing, the inference is not on the asymptotic properties of forecasts, but on their population finite sample properties. We acknowledge that the philosophy of this inference framework remains a point of contention, but it does tackle three important evaluation difficulties in this paper. First, it allows for evaluation of forecast intervals that are not parametrically derived. The density evaluation methods developed in well-known studies such as Diebold, Gunther, Tay (1998), Corradi and Swanson (2006a) and references within Corradi and Swanson (2006b) require that the forecast distributions be parametrically specified. Giacomini and White's (2006) method overcomes this challenge by allowing comparisons among parametric, semiparametric and nonparametric forecasts. As a result, in the cases of semiparametric and nonparametric forecasts, it also allows comparison of models with predictors of different dimensions, as evident in our exercise. Second, by comparing the finite sample properties of RS forecast intervals derived from different models, we avoid rejecting models that are mis-specified,14 but are nonetheless good approximations useful for forecasting. Finally, we can individually (though not jointly) test whether the forecast intervals differ in terms of empirical coverages and lengths, for the given estimation sample, and are not confined to focus only on empirical coverages or holistic properties of forecast distribution, such as probability integral transform.

3.1  Test of Equal Empirical Coverages

Suppose the sample size available to the researcher is $ T$ and all data are collected in a vector $ \mathbf{W}_{t}$. Our inference procedure is based on a rolling estimation scheme, with the size of the rolling window fixed while $ T\rightarrow\infty$. Let $ T=R+N$ and $ R$ be the size of the rolling window. For each horizon $ h$ and model $ m$, a sequence of $ N(h)=N+1-h$ $ \alpha $-coverage forecast intervals are generated using rolling data: $ \{\mathbf{W} _{t}\}_{t=1}^{R}$ for forecast for date $ R+h$, $ \{\mathbf{W}_{t}\}_{t=2} ^{R+1}$ for forecast for date $ R+h+1$, and so on, until forecast for date $ T$ is generated using $ \{\mathbf{W}_{t}\}_{t=N(h)}^{R+N(h)-1}$.

Under this fixed-sample-size rolling scheme, for each finite $ h$ we have $ N(h)$ observations to compare the empirical coverages and lengths across $ m$ models ( $ m=1, 2,...,7$). By fixing $ R$, we allow the finite sample properties of the forecast intervals to be preserved as $ T\rightarrow\infty$. Thus, the forecast intervals and the associated forecast losses are simply functions of a finite and fixed number of random variables. We are interested in approximating the population moments of these objects by taking $ N(h)\rightarrow\infty$. A loose analogy would be finding the finite-sample properties of a certain parameter estimator when the sample size is fixed at $ R$, by a bootstrap with an arbitrarily large number of bootstrap replications.

We conduct individual tests for the empirical coverages and lengths. In each test, we define a corresponding forecast loss, propose a test statistic and derive its asymptotic distribution. As defined in equation (10), let $ \widehat{I}^{\alpha}_{m,\tau+h}$ be the $ h-$horizon ahead RS forecast interval of model $ m$ with a nominal coverage of $ \alpha$. For out-of-sample forecast evaluation, we require $ \widehat{I}^{\alpha}_{m,\tau+h}$ to be constructed using data from $ t=\tau-R+1$ to $ t=\tau$. The coverage accuracy loss is defined as:

$\displaystyle CL_{m,h}^{\alpha}=\left[ P(Y_{\tau+h}\in\widehat{I}^{\alpha}_{m,\tau +h})-\alpha\right] ^{2}.$ (11)

For economic models ($ m=1,...,6$), the goal is to compare the coverage accuracy loss of RS forecast intervals of model $ m$ with that of the random walk ($ m=7$). The null and alternative hypotheses are:

$\displaystyle H_{0}$ $\displaystyle : \Delta CL_{m,h}^{\alpha}\equiv CL_{7,h}^{\alpha}-CL_{m,h}^{\alpha }=0$
$\displaystyle H_{A}$ $\displaystyle : \Delta CL_{m,h}^{\alpha}\ne0.$

Define the sample analog of the coverage accuracy loss in equation (11):

$\displaystyle \widehat{CL}_{m,h}^{\alpha}=\left( N(h)^{-1}\sum_{\tau=R}^{T-h}1(Y_{\tau+h} \in\widehat{I}^{\alpha}_{m,\tau+h})-\alpha\right) ^{2},$

where $ 1(Y_{\tau+h}\in\widehat{I}^{\alpha}_{m,\tau+h})$ is an index function that equals one when $ Y_{\tau+h}\in\widehat{I}^{\alpha}_{m,\tau+h}$, and equals zero otherwise. Applying the asymptotic test of Giacomini and White (2006) to the sequence $ \{1(Y_{\tau+h}\in\widehat{I}^{\alpha}_{m,\tau +h})\}_{\tau=R}^{T-h}$ and applying the Delta method, we can show that

$\displaystyle \sqrt{N(h)}(\Delta\widehat{CL}_{m,h}^{\alpha}-\Delta CL_{m,h}^{\alpha })\overset{d}{\rightarrow}N(0,\Gamma_{m,h}^{^{\prime}}\Omega_{m,h}\Gamma _{m,h}),$ (12)

where $ \overset{d}{\rightarrow}$ denotes convergence in distribution, and $ \Omega_{m,h}$ is the long-run covariance matrix between $ 1(Y_{\tau+h} \in\widehat{I}^{\alpha}_{m,\tau+h})$ and $ 1(Y_{\tau+h}\in\widehat{I}^{\alpha }_{7,\tau+h})$. The matrix $ \Gamma_{m,h}$ is defined as:

$\displaystyle \Gamma_{m,h}\equiv\left[ \begin{array}[c]{cc} 2\left( P\left( Y_{\tau+h}\in\widehat{I}^{\alpha}_{m,\tau+h}\right) -\alpha\right) & 2\left( P\left( Y_{\tau+h}\in\widehat{I}^{\alpha}_{7,\tau +h}\right) -\alpha\right) \end{array} \right] ^{\prime}.$

$ \Gamma_{m,h}$ can be estimated consistently by its sample analog $ \widehat{\Gamma}_{m,h}$, while $ \Omega_{m,h}$ can be estimated by some HAC estimator $ \widehat{\Omega}_{m,h}$, such as Newey and West (1987).15The test statistic for coverage test is defined as:

$\displaystyle Ct_{m,h}^{\alpha}\equiv\frac{\sqrt{N(h)}\Delta\widehat{CL}_{m,h}^{\alpha} }{\sqrt{\widehat{\Gamma}_{m,h}^{^{\prime}}\widehat{\Omega}_{m,h} \widehat{\Gamma}_{m,h}}}\overset{d}{\rightarrow}N(0,1)$ (13)

3.2  Test of Equal Empirical Lengths

Define the length loss as:

$\displaystyle LL^{\alpha}_{m,h}\equiv E\left[ leb\left( \widehat{I}^{\alpha}_{m,\tau +h}\right) \right] ,$ (14)

where $ leb(\cdot)$ is the Lesbesgue measure. To compare the length loss of RS forecast intervals of economic models $ m=1, 2,...,6$ with that of the random walk ($ m=7)$, the null and alternative hypotheses are:

$\displaystyle H_{0}$ $\displaystyle : \Delta LL_{m,h}^{\alpha}\equiv LL_{7,h}^{\alpha}-LL_{m,h}^{\alpha }=0$
$\displaystyle H_{A}$ $\displaystyle : \Delta LL_{m,h}^{\alpha}\ne0.$

The sample analog of the length loss for model $ m$ is defined as:

$\displaystyle \widehat{LL}_{m,h}^{\alpha}=N(h)^{-1}\sum_{\tau=R}^{T-h}leb(\widehat {I}^{\alpha}_{m,\tau+h}).$

Directly applying the test of Giacomini and White (2006), we have

$\displaystyle \sqrt{N(h)}(\Delta\widehat{LL}_{m,h}^{\alpha}-\Delta LL_{m,h}^{\alpha })\overset{d}{\rightarrow}N(0,\Sigma_{m,h}),$ (15)

where $ \Sigma_{m,h}$ is the long-run variance of $ leb\left( \widehat {I}^{\alpha}_{7,\tau+h}\right) -leb\left( \widehat{I}^{\alpha}_{m,\tau +h}\right) $ . Let $ \widehat{\Sigma}_{m,h}$ be the HAC estimator of $ \Sigma_{m,h}$. The test statistic for empirical length is defined as:

$\displaystyle Lt_{m,h}^{\alpha}\equiv\frac{\sqrt{N(h)}\Delta\widehat{LL}_{m,h}^{\alpha} }{\sqrt{\widehat{\Sigma}_{m,h}}}\overset{d}{\rightarrow}N(0,1).$ (16)

3.3  Discussion

The coverage accuracy loss function is symmetric in our paper. In practice, an asymmetric loss function may be better when looking for an exchange rate forecast model to help make policy or business decisions. Under-coverage is arguably a more severe problem than over-coverage in practical situations. However, the focus of this paper is the disconnect between economic fundamentals and the exchange rate. Our goal is to investigate which model comes closer to the data: the random walk or fundamental-based models. It is not critical in this case whether coverage inaccuracy comes from the under- or over-coverage. We acknowledge that the use of symmetric coverage loss remains a caveat, especially since we are using the coverage accuracy test as a pre-test for the tests of length. Clearly, there is a tradeoff between the empirical coverage and the length of forecast intervals. Given the same center,16 intervals with under-coverage have shorter lengths than intervals with over-coverage. In this case, the length test is in favor of models that systematically under-cover the targeted nominal coverage when compared to a model that systematically over-covers. This problem cannot be detected by the coverage accuracy test with symmetric loss function because over- and under-coverage are treated equally. However, our results in section 4 show that there is no evidence of systematic under-coverage for the economic models considered in this paper. For instance, in Table 1, one-month-ahead ($ h=1$) forecast intervals over-cover the nominal coverage (90%) for eight out of twelve exchange rates.17 Note that under-coverage does not guarantee shorter intervals either in our paper, because forecast intervals of different models usually have different centers.18 In addition, we also compare the coverage of economic models and the random walk directly in an exercise not reported in this paper. There is no evidence that the coverage of economic models is systematically smaller than that of the random walk.19

As we have mentioned, comparisons across models can also be done at the distribution level. We choose interval forecasts for two reasons. First, interval forecasts have been widely used and reported by the practitioners. For instance, the Bank of England calculates forecast intervals of inflation in its inflation reports. Second, compared to evaluation metrics for density forecasts, the empirical coverage and length loss functions of interval forecasts, and the subsequent interpretations of test rejection/acceptance are more intuitive.


4.  Results

We apply RS forecast intervals for each model for a given nominal coverage of $ \alpha=0.9$. There is no particular reason why we chose 0.9 as the nominal coverage. Some auxiliary results show that our qualitative findings do not depend on the choice of $ \alpha$. Due to different sample sizes across countries, we choose different sizes for the rolling window ($ R$) for different countries. Our rule is very simple: for countries with $ T\ge300$, we choose $ R=200$, otherwise we set $ R=150$.20 Again, from our experience, tampering with $ R$ does not change the qualitative results, unless $ R$ is chosen to be unusually big or small.

For time horizons $ h=1,3,6,9,12$ and models $ m=1,...,7$, we construct a sequence of $ N(h)$ 90% forecast intervals $ \{\widehat{I}^{0.9}_{m,\tau +h}\}_{\tau=R}^{T-h}$ for the $ h$-horizon change of the exchange rate $ s_{t+h}-s_{t}$. Then we compare economic models and the random walk by computing empirical coverages, lengths and test statistics $ Ct_{m,h}^{0.9}$ and $ Lt_{m,h}^{0.9}$ as described in section 3. We first report the results of our benchmark model. After that, results of alternative models are reported and discussed.

4.1  Results of Benchmark Model

Table 1 shows results of the benchmark Taylor rule model. For each time horizon $ h$ and exchange rate, the first column (Cov.) reports the empirical coverage for the given nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals (the distance between upper and lower bounds). The length is multiplied by 100 and therefore expressed in terms of the percentage change of the exchange rate. For instance, the empirical coverage and length of the one-month-ahead forecast interval for the Australian dollar are $ 0.895$ and $ 7.114$, respectively. It means that on average, with a chance of 89.5%, the one-month-ahead change of AUD/USD lies in an interval with length $ 7.114$%. We use superscripts $ a$, $ b$, and $ c$ to denote that the null hypothesis of equal empirical coverage accuracy/length is rejected in favor of the Taylor rule model at a confidence level of 10%, 5%, and 1% respectively. Superscripts $ x$, $ y$, and $ z$ are used for rejections in favor of the random walk analogously.

We summarize our findings in three panels. In the first panel ((1) Coverage Test), the row of "Model Better" reports the number of exchange rates that the Taylor rule model has more accurate empirical coverages than the random walk. The row of "RW Better" reports the number of exchange rates for which the random walk outperforms the Taylor rule model under the same criterion. In the second panel ((2) Length Test Given Equal Coverage Accuracy), a better model is the one with tighter forecast intervals given equal coverage accuracy. In the last panel ((1)+(2)), a better model is the one with either more accurate coverages, or tighter forecast intervals given equal coverage accuracy.

For most exchange rates and time horizons, the Taylor rule model and the random walk model have statistically equally accurate empirical coverages. The null hypothesis of equal coverage accuracy is rejected in only six out of sixty tests (two rejections each at horizons 6, 9, and 12). Five out of six rejections are in favor of the Taylor rule model. That is, the empirical coverage of the Taylor rule model is closer to the nominal coverage than those of the random walk. However, based on the number of rejections (5) in a total of sixty tests, there is no strong evidence that the Taylor rule model can generate more accurate empirical coverages than the random walk.

In cases where the Taylor rule model and the random walk have equally accurate empirical coverages, the Taylor rule model generally has equal or significantly tighter forecast intervals than the random walk. In forty-two out of fifty-four cases, the null hypothesis of equally tight forecast intervals is rejected in favor of the Taylor rule model. In contrast, the null hypothesis is rejected in only three cases in favor of the random walk. The evidence of exchange rate predictability is more pronounced at longer horizons. At horizon twelve ($ h=12$), for all cases where empirical coverage accuracies between the random walk and the Taylor rule model are statistically equivalent, the Taylor rule model has significantly tighter forecast intervals than the random walk.

As for each individual exchange rate, the benchmark Taylor rule model works best for the French Franc, the Deutschmark, the Dutch Guilder, the Swedish Krona, and the British Pound: for all time horizons, the model has tighter forecast intervals than the random walk, while their empirical coverages are statistically equally accurate. The Taylor rule model performs better than the random walk in most horizons for the remaining exchange rates except the Portuguese Escudo, for which the Taylor rule model outperforms the random walk only at long horizons.

4.2  Results of Alternative Models

Five alternative economic models are also compared with the random walk: three alternative Taylor rule models that are studied in Molodtsova and Papell (2009), the PPP model, and the monetary model. Tables 2-6 report results of these alternative models.

In general, results of coverage tests do not show strong evidence that economic models can generate more accurate coverages than the random walk at either short or long horizons. However, after considering length tests, we find that economic models perform better than the random walk, especially at long horizons. Taylor rule model 4 (the benchmark model with interest rate smoothing Table 4) and the PPP model (Table 5) perform the best among alternative models. Results of these two models are very similar to that of the benchmark Taylor rule model. At horizon twelve, both models outperform the random walk for most exchange rates under our out-of-sample forecast interval evaluation criteria. The performance of Taylor rule model 2 (Table 2) and 3 (Table 3) is relatively less impressive than other models, but for more than half of the exchange rates, the economic models outperform the random walk at several horizons in out-of-sample interval forecasts.

Comparing the benchmark Taylor rule model, the PPP model and the monetary model, the performance of the PPP model (Table 5) is worse than the other two models at short horizons. Compared to the Taylor rule and PPP models, the monetary model outperforms the random walk for a smaller number of exchange rates at horizons 6, 9, and 12. Overall, the benchmark Taylor rule model seems to perform slightly better than the monetary and PPP models. Molodtsova and Papell (2009) find similar results in their point forecasts.

Table 7 shows results with heterogeneous Taylor rules.21 In this model, we relaxed the assumption that the Taylor rule coefficients are the same in the home and foreign countries. We replace $ \pi_{t}-\pi_{t}^{\ast }$ and $ y_{t}^{gap}-y_{t}^{gap\ast}$ in matrix $ \mathbf{X}_{1,t}$ of the benchmark model with $ \hat{\delta}_{\pi}\pi_{t}-\hat{\delta}_{\pi}^{\ast} \pi_{t}^{\ast}$ and $ \hat{\delta}_{y}y_{t}^{gap}-\hat{\delta}_{y}^{\ast} y_{t}^{gap\ast}$ , where $ \hat{\delta}_{\pi}$, $ \hat{\delta}_{\pi}^{\ast}$, $ \hat{\delta}_{y}$, and $ \hat{\delta}_{y}^{\ast}$ are Taylor rule coefficients estimated from the data of home and foreign countries. The main findings in the benchmark model also hold in Table 7.

4.3  Discussion

After Mark (1995) first documents exchange rate predictability at long horizons, long-horizon exchange rate predictability has become a very active area in the literature. With panel data, Engel, Mark, and West (2007) recently show that the long-horizon predictability of the exchange rate is relatively robust in the exchange rate forecasting literature. We find similar results in our interval forecasts. The evidence of long-horizon predictability seems robust across different models and currencies when both empirical coverage and length tests are used. At horizon twelve, all economic models outperform the random walk for six exchange rates: the Australian Dollar, French Franc, Italian Lira, Japanese Yen, Swedish Krona, and the British Pound in the sense that interval lengths of economic models are smaller than those of the random walk, given equivalent coverage accuracy. This is true only for the Danish Kroner and Swiss Franc at horizon one. We also notice that there is no clear evidence of long-horizon predictability based on the tests of empirical coverage accuracy only.

Molodtsova and Papell (2009) find strong out-of-sample exchange rate predictability for Taylor rule models even at the short horizon. In our paper, the evidence for exchange rate predictability at short horizons is not very strong. This finding may be a result of some assumptions we have used to simplify our computation. For instance, an $ \alpha$-coverage forecast interval in our paper is always constructed using the $ (1-\alpha)/2$ and $ (1+\alpha)/2$ quantiles. Alternatively, we can choose quantiles that minimize the length of intervals, given the nominal coverage.22 In addition, the development of more powerful testing methods may also be helpful. The evidence of exchange rate predictability in Molodtsova and Papell (2009) is partly driven by the testing method recently developed by Clark and West (2006, 2007). We acknowledge that whether or not short-horizon results can be improved remains an interesting question, but do not pursue this in the current paper. The purpose of this paper is to show the connection between the exchange rate and economic fundamentals from an interval forecasting perspective. Predictability either at short- or long-horizons will serve this purpose.

Though we find that economic fundamentals are helpful for forecasting exchange rates, we acknowledge that exchange rate forecasting in practice is still a difficult task. The forecast intervals from economic models are statistically tighter than those of the random walk, but they remain fairly wide. For instance, the distance between the upper and lower bound of three-month-ahead forecast intervals is usually a 20% change of the exchange rates. Figures 1-3 show the length of forecast intervals generated by the benchmark Taylor rule model and the random walk for the British Pound, the Deutschmark, and the Japanese Yen at different horizons.23 At the horizon of 12 months, the length of forecast intervals in the Taylor rule model is usually smaller than that in the random walk. However, at shorter horizons, such as 1 month, the difference is quantitatively small.


5.  Conclusion

There is a growing strand of literature that uses Taylor rules to model exchange rate movements. Our paper contributes to the literature by showing that Taylor rule fundamentals are useful in forecasting the distribution of exchange rates. We apply Robust Semiparametric forecast intervals of Wu (2009) to a group of Taylor rule models for twelve OECD exchange rates. The forecast intervals generated by the Taylor rule models are in general tighter than those of the random walk, given that these intervals cover the realized exchange rates equally well. The evidence of exchange rate predictability is more pronounced at longer horizons, a result that echoes previous long-horizon studies such as Mark (1995). The benchmark Taylor rule model is also found to perform better than the monetary and PPP models based on out-of-sample interval forecasts.

Though we find some empirical support for the connection between the exchange rate and economic fundamentals, we acknowledge that the detected connection is weak. The reductions of the lengths of forecast intervals are quantitatively small, though they are statistically significant. Forecasting exchange rates remains a difficult task in practice. Engel and West (2005) argue that as the discount factor gets closer to one, present value asset pricing models place greater weight on future fundamentals. Consequently, current fundamentals have very weak forecasting power and exchange rates appear to follow approximately a random walk. Under standard assumptions in Engel and West (2005), the Engel-West theorem does not imply that exchange rates are more predictable at longer horizons or that economic models can outperform the random walk in forecasting exchange rates based on out-of-sample interval forecasts. However, modifications to these assumptions may be able to reconcile the Engel-West explanation with empirical findings of exchange rate predictability. For instance, Engel, Wang, and Wu (2008) find that when there exist stationary, but persistent, unobservable fundamentals, for example risk premium, the Engel-West explanation predicts long-horizon exchange rate predictability in point forecasts, though the exchange rate still approximately follows a random walk at short horizons. It would also be of interest to study conditions under which our findings in interval forecasts can be reconciled with the Engel-West theorem.

We believe other issues, such as parameter instability (Rossi, 2005), nonlinearity (Kilian and Taylor, 2003), real time data (Faust, Rogers, and Wright, 2003, Molodtsova, Nikolsko-Rzhevskyy, and Papell, 2008a, 2008b), and model selection (Sarno and Valente, forthcoming) are all contributing to the Meese-Rogoff puzzle. Panel data are also found helpful in detecting exchange rate predictability, especially at long horizons. For instance, see Mark and Sul (2001), Engel, Mark, and West (2007), and Rogoff and Stavrakeva (2008). It would be interesting to incorporate these studies into interval forecasting. We leave these extensions for future research.

 

Table 1.-Panel 1:  Results of Benchmark Taylor Rule Model
 Cov. h=1 Leng. h=1 Cov. h=3 Leng. h=3 Cov. h=6 Leng. h=6 Cov. h=9 Leng. h=9 Cov. h=12 Leng. h=12

Australian Dollar

 0.895  7.114  0.888  14.209c 0.959  21.140  0.942  26.613  0.963  29.175c

Canadian Dollar

 0.814  3.480  0.794  6.440c  0.738  8.483c  0.675  8.669c  0.596x 9.707c 

Danish Kroner

 0.920  8.676c 0.939  17.415c 0.954  26.198  0.922  28.712c 0.968  37.123c

French Franc

 0.912  8.921c 0.860  15.728c 0.928c 26.007c 0.957  29.924c 0.934  36.883c

Deutschmark

 0.927  8.327c 0.879  18.634c 0.894  27.923c 0.960a 33.734c 0.969  39.618c

Italian Lira

 0.899  8.291c 0.875  18.305  0.910  26.788c 0.846  32.545c 0.874  37.151c

Japanese Yen

 0.915  9.633z 0.909  19.762  0.892  28.451c 0.932  33.793c 0.883  37.728c

Dutch Guilder

 0.917  8.726c 0.907  18.615c 0.933  27.458c 0.941b 30.902c 0.959a 40.177c

Portuguese Escudo

 0.901  8.580z 0.928  18.758z 0.894c 23.552c 0.825  27.086  0.867  32.092c

Swedish Krona

 0.839  7.360c 0.860  15.413c 0.874  23.930c 0.820  28.090c 0.834  37.432c

Swiss Franc

 0.947  9.358c 0.916  19.655  0.963  26.553c 0.963  30.780c 0.899  35.008c

British Pound

 0.919  8.413a 0.923  16.592c 0.912  23.317c 0.900  26.942c 0.855  25.905c

Note: –h denotes forecast horizons for monthly data. –For each horizon (h), the first column (Cov.) reports empirical coverages given a nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals in terms of percentage change of the exchange rate. Empirical coverages and lengths are averages across N(h) out-of-sample trials. –Superscripts a, b, c in the column of Cov. (Leng.) denote rejections of equal coverage accuracy (equal length) in favor of the economic model at a 10%, 5% and 1% confidence level respectively. Superscripts x, y, z are defined analogously for rejections in favor of the random walk

Table 1.-Panel 2:  Results of Benchmark Taylor Rule Model, Coverage Test
  h=1 h=3 h=6 h=9 h=12
Model Better 0 0 2 2 1
RW Better 0 0 0 0 1

Note: In this panel, a better model is the one with more accurate empirical coverages. RW is the abbreviation of Random Walk.

Table 1.-Panel 3:  Results of Benchmark Taylor Rule Model, Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 8 8 8 8 10
RW Better 2 1 0 0 0

Note: In this panel, a better model is the one with tighter forecast intervals given equal coverage accuracy.

Table 1.-Panel 4:  Results of Benchmark Taylor Rule Model, Coverage Test and Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 8 8 10 10 11
RW Better 2 1 0 0 1

Note: In this panel, a better model is the one with either more accurate coverages or tighter forecast intervals given equal coverage accuracy.

Table 2.-Panel 1:  Results of Benchmark Taylor Rule Model Two
 Cov. h=1 Leng. h=1 Cov. h=3 Leng. h=3 Cov. h=6 Leng. h=6 Cov. h=9 Leng. h=9 Cov. h=12 Leng. h=12

Australian Dollar

 0.884  7.146y 0.899  15.086c 0.928  21.327  0.901  27.329  0.872  30.815b

Canadian Dollar

 0.825  3.442c 0.783  6.321c  0.814  8.490c  0.858  10.034c 0.825  11.921c

Danish Kroner

 0.915  8.753a 0.939  17.764c 0.954  27.479z 0.953  33.426y 0.942  40.717 

French Franc

 0.951  9.042c 0.930  18.783  0.949c 29.161c 0.936  34.994c 0.868  42.081c

Deutschmark

 0.917  9.090  0.869  19.217  0.952  29.746  0.941a 39.093a 0.980  44.571z

Italian Lira

 0.928  9.196  0.875  18.322  0.895  26.926c 0.869  35.883c 0.898a 41.235z

Japanese Yen

 0.915  9.568x 0.914  19.734  0.912  29.344c 0.937  36.834  0.942  44.385c

Dutch Guilder

 0.908  8.586c 0.888  18.782c 0.962  29.777  0.990  39.507z 0.990  47.514z

Portuguese Escudo

 0.916  8.005  0.957  17.924z 0.909c 24.270b 0.889  28.533z 0.883a 35.338c 

Swedish Krona

 0.867  7.624  0.860  16.132  0.857  24.500c 0.837  32.825  0.811  37.772c

Swiss Franc

 0.941  9.953b 0.928  20.105  0.982  29.758c 0.994  38.267z 0.962  45.965z

British Pound

 0.919  8.627z 0.933  17.334c 0.922  26.227c 0.937  31.044c 0.957  36.397c

Note: –h denotes forecast horizons for monthly data. –For each horizon (h), the first column (Cov.) reports empirical coverages given a nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals in terms of percentage change of the exchange rate. Empirical coverages and lengths are averages across N(h) out-of-sample trials. –Superscripts a, b, c in the column of Cov. (Leng.) denote rejections of equal coverage accuracy (equal length) in favor of the economic model at a 10%, 5% and 1% confidence level respectively. Superscripts x, y, z are defined analogously for rejections in favor of the random walk.

Table 2.-Panel 2:  Results of Benchmark Taylor Rule Model Two, Coverage Test
  h=1 h=3 h=6 h=9 h=12
Model Better 0 0 2 1 2
RW Better 0 0 0 0 0

Note: In this panel, a better model is the one with more accurate empirical coverages. RW is the abbreviation of Random Walk.

Table 2.-Panel 3:  Results of Benchmark Taylor Rule Model Two, Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 5 5 6 4 6
RW Better 3 1 1 4 3

Note: In this panel, a better model is the one with tighter forecast intervals given equal coverage accuracy.

Table 2.-Panel 4:  Results of Benchmark Taylor Rule Model Two, Coverage Test and Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 5 5 8 5 8
RW Better 3 1 1 4 3

Note: In this panel, a better model is the one with either more accurate coverages or tighter forecast intervals given equal coverage accuracy.

Table 3.-Panel 1:  Results of Benchmark Taylor Rule Model Three
 Cov. h=1 Leng. h=1 Cov. h=3 Leng. h=3 Cov. h=6 Leng. h=6 Cov. h=9 Leng. h=9 Cov. h=12 Leng. h=12

Australian Dollar

 0.884  7.229z 0.899  15.055c 0.881  21.055  0.885  26.359c 0.867  30.234c

Canadian Dollar

 0.831  3.453b 0.789  6.408c  0.814  8.629c  0.864  10.220c 0.819  11.971c

Danish Kroner

 0.920  8.753b 0.934  17.649c 0.949  27.523z 0.948  33.307  0.936  40.070 

French Franc

 0.951  9.171  0.740  14.488c 0.722  20.313c 0.915  35.562a 0.813  41.350c 

Deutschmark

 0.908  9.020  0.897  19.303  0.914  29.676  0.901c 37.291c 0.878  44.761z

Italian Lira

 0.928  8.900a 0.875  17.206c 0.872  26.674c 0.839  34.819c 0.787  39.569c

Japanese Yen

 0.905  9.179c 0.878  18.907c 0.892  25.883c 0.927  31.259c 0.894  37.049c

Dutch Guilder

 0.927  8.910  0.907  19.204a 0.952  29.426a 0.951a 36.896c 0.959  46.321z

Portuguese Escudo

 0.930  7.961  0.942  16.883c 0.955a 23.786  0.905  26.620c 0.850  33.745c

Swedish Krona

 0.867  7.316c 0.848  15.017c 0.840  23.241c 0.791  29.265c 0.757  33.751c

Swiss Franc

 0.929  9.761b 0.922  19.517c 0.939  28.437b 0.926c 37.519  0.911  45.619 

British Pound

 0.929  8.239a 0.939  16.213c 0.927  23.951c 0.905  28.720c 0.952  34.900c

Note: –h denotes forecast horizons for monthly data. –For each horizon (h), the first column (Cov.) reports empirical coverages given a nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals in terms of percentage change of the exchange rate. Empirical coverages and lengths are averages across N(h) out-of-sample trials. –Superscripts a, b, c in the column of Cov. (Leng.) denote rejections of equal coverage accuracy (equal length) in favor of the economic model at a 10%, 5% and 1% confidence level respectively. Superscripts x, y, z are defined analogously for rejections in favor of the random walk.

Table 3.-Panel 2:  Results of Benchmark Taylor Rule Model Three, Coverage Test
  h=1 h=3 h=6 h=9 h=12
Model Better 0 0 1 3 0
RW Better 0 0 0 0 0

Note: In this panel, a better model is the one with more accurate empirical coverages. RW is the abbreviation of Random Walk.

Table 3.-Panel 3:  Results of Benchmark Taylor Rule Model Three, Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 7 11 8 8 8
RW Better 1 0 1 0 2

Note: In this panel, a better model is the one with tighter forecast intervals given equal coverage accuracy.

Table 3.-Panel 4:  Results of Benchmark Taylor Rule Model Three, Coverage Test and Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 7 11 9 11 8
RW Better 1 0 1 0 2

Note: In this panel, a better model is the one with either more accurate coverages or tighter forecast intervals given equal coverage accuracy.

Table 4.-Panel 1:  Results of Benchmark Taylor Rule Model Four
 Cov. h=1 Leng. h=1 Cov. h=3 Leng. h=3 Cov. h=6 Leng. h=6 Cov. h=9 Leng. h=9 Cov. h=12 Leng. h=12

Australian Dollar

 0.895  7.119  0.888  14.424c 0.928  20.966  0.927  25.304c 0.872  27.492c

Canadian Dollar

 0.814  3.425c 0.771  6.366c  0.698  8.019c  0.651  8.631c  0.494y  7.693c 

Danish Kroner

 0.920  8.703c 0.929  17.536c 0.964  26.025  0.984x 30.891c 0.963  36.545c

French Franc

 0.892  8.361c 0.870  16.079c 0.938c 25.950c 0.883  30.016c 0.791  35.755c

Deutschmark

 0.927  8.314c 0.879  18.652c 0.894  26.803c 0.931c 33.350c 0.969  36.393c

Italian Lira

 0.891  8.663c 0.838  17.575c 0.865  26.387c 0.746  32.270c 0.724  36.422c

Japanese Yen

 0.905  9.157c 0.863  18.708c 0.866  24.417c 0.869  28.730c 0.851  31.470c

Dutch Guilder

 0.936  8.815  0.897  18.368c 0.914  26.700c 0.931c 30.036c 0.796  29.462c

Portuguese Escudo

 0.901  8.525z 0.913a 17.110  0.939c 23.461c 0.889  27.096a 0.917  28.778c

Swedish Krona

 0.861  7.289c 0.860  15.321c 0.869  23.340c 0.773  27.198c 0.728  31.843c

Swiss Franc

 0.947  9.149c 0.940  19.782a 0.811  22.796c 0.808  26.148c 0.671  26.683c

British Pound

 0.919  8.113a 0.913  15.765c 0.875  21.679  0.825  27.312c 0.839  29.081c

Note: –h denotes forecast horizons for monthly data. –For each horizon (h), the first column (Cov.) reports empirical coverages given a nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals in terms of percentage change of the exchange rate. Empirical coverages and lengths are averages across N(h) out-of-sample trials. –Superscripts a, b, c in the column of Cov. (Leng.) denote rejections of equal coverage accuracy (equal length) in favor of the economic model at a 10%, 5% and 1% confidence level respectively. Superscripts x, y, z are defined analogously for rejections in favor of the random walk.

Table 4.-Panel 2:  Results of Benchmark Taylor Rule Model Four, Coverage Test
  h=1 h=3 h=6 h=9 h=12
Model Better 0 1 2 2 0
RW Better 0 0 0 1 1

Note: In this panel, a better model is the one with more accurate empirical coverages. RW is the abbreviation of Random Walk.

Table 4.-Panel 3:  Results of Benchmark Taylor Rule Model Four, Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 9 11 8 9 11
RW Better 1 0 0 0 0

Note: In this panel, a better model is the one with tighter forecast intervals given equal coverage accuracy.

Table 4.-Panel 4:  Results of Benchmark Taylor Rule Model Four, Coverage Test and Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 9 12 10 11 11
RW Better 1 0 0 1 1

Note: In this panel, a better model is the one with either more accurate coverages or tighter forecast intervals given equal coverage accuracy.

Table 5.-Panel 1:  Results of Purchasing Power Parity Model
 Cov. h=1 Leng. h=1 Cov. h=3 Leng. h=3 Cov. h=6 Leng. h=6 Cov. h=9 Leng. h=9 Cov. h=12 Leng. h=12

Australian Dollar

 0.895  7.114z 0.883  15.558  0.912  21.311  0.880  26.120c 0.856  30.316c

Canadian Dollar

 0.819  3.570z 0.806  6.872  0.767  9.615  0.728  11.078c 0.615  12.306c

Danish Kroner

 0.925  8.697c 0.939  18.333  0.938  25.887c 0.937  31.673c 0.957  37.447c

French Franc

 0.922  8.904c 0.940  18.029c 0.918c 25.786c 0.904  29.789c 0.802  34.209c

Deutschmark

 0.936  9.079  0.935  18.797c 0.942  27.677c 1.000  33.585c 0.990  40.570c

Italian Lira

 0.913  8.780c 0.868  17.767c 0.827  25.044c 0.769  30.190c 0.772  34.806c

Japanese Yen

 0.920  9.662z 0.899  19.903  0.912  28.689c 0.932  33.973c 0.899  38.568c

Dutch Guilder

 0.936  8.862y 0.935  18.904c 0.952  27.928c 1.000  33.468c 0.990  41.812c

Portuguese Escudo

 0.916  8.421y 0.928  19.027y 0.924c 23.918  0.857  27.450  0.867  32.467c

Swedish Krona

 0.861  7.541c 0.876  16.089  0.886  24.345c 0.855  31.744b 0.799  37.943c

Swiss Franc

 0.941  9.708c 0.946  19.694b 0.976  27.197c 0.950b 31.725c 0.880  36.235c

British Pound

 0.934  8.571y 0.933  16.954c 0.932  24.064c 0.947  28.761c 0.925a 31.372c

Note: –h denotes forecast horizons for monthly data. –For each horizon (h), the first column (Cov.) reports empirical coverages given a nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals in terms of percentage change of the exchange rate. Empirical coverages and lengths are averages across N(h) out-of-sample trials. –Superscripts a, b, c in the column of Cov. (Leng.) denote rejections of equal coverage accuracy (equal length) in favor of the economic model at a 10%, 5% and 1% confidence level respectively. Superscripts x, y, z are defined analogously for rejections in favor of the random walk.

Table 5.-Panel 2:  Results of Purchasing Power Parity Model, Coverage Test
  h=1 h=3 h=6 h=9 h=12
Model Better 0 0 2 1 1
RW Better 0 0 0 0 0

Note: In this panel, a better model is the one with more accurate empirical coverages. RW is the abbreviation of Random Walk.

Table 5.-Panel 3:  Results of Purchasing Power Parity Model, Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 5 6 8 10 11
RW Better 6 1 0 0 0

Note: In this panel, a better model is the one with tighter forecast intervals given equal coverage accuracy.

Table 5.-Panel 4:  Results of Purchasing Power Parity Model, Coverage Test and Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 5 6 10 11 12
RW Better 6 1 0 0 0

Note: In this panel, a better model is the one with either more accurate coverages or tighter forecast intervals given equal coverage accuracy.

Table 6.-Panel 1:  Results of Monetary Model
 Cov. h=1 Leng. h=1 Cov. h=3 Leng. h=3 Cov. h=6 Leng. h=6 Cov. h=9 Leng. h=9 Cov. h=12 Leng. h=12

Australian Dollar

 0.879  7.108  0.848  15.151  0.830  20.090  0.770  24.642c 0.745  30.099b

Canadian Dollar

 0.842  4.027x 0.829  7.492  0.744  10.518  0.645  10.689b 0.675  12.993c

Danish Kroner

 0.905  8.770b 0.893  17.943  0.897  25.017c 0.853  28.581c 0.809  32.504c

French Franc

 0.922  8.791c 0.910  18.237c 0.949b 26.322c 0.957  31.032c 0.956  35.971c

Deutschmark

 0.908  8.595  0.841  17.436c 0.808  24.622c 0.772  28.052c 0.704  31.364c

Italian Lira

 0.913  8.858c 0.882  18.439b 0.925  26.585c 0.931  34.857c 0.913  40.885c

Japanese Yen

 0.930  9.556  0.919  19.374c 0.887  28.614c 0.864  33.401c 0.809  36.520c

Dutch Guilder

 0.917  8.753a 0.916  19.408  0.962  29.149b 0.970  38.173  0.898c 41.716c

Portuguese Escudo

 0.901  8.086  0.986  18.484  0.985  24.744  0.984  27.230  1.000  34.222 

Swedish Krona

 0.850  7.504a 0.848  17.097x 0.811  23.878c 0.826  31.287  0.805  34.710c

Swiss Franc

 0.905  9.078c 0.820  17.020c 0.732  21.212c 0.609  22.741c 0.513x 23.225c

British Pound

 0.909  7.811c 0.882  14.945c 0.787  20.788c 0.677  24.311c 0.656  26374c 

Note: –h denotes forecast horizons for monthly data. –For each horizon (h), the first column (Cov.) reports empirical coverages given a nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals in terms of percentage change of the exchange rate. Empirical coverages and lengths are averages across N(h) out-of-sample trials. –Superscripts a, b, c in the column of Cov. (Leng.) denote rejections of equal coverage accuracy (equal length) in favor of the economic model at a 10%, 5% and 1% confidence level respectively. Superscripts x, y, z are defined analogously for rejections in favor of the random walk.

Table 6.-Panel 2:  Results of Monetary Model, Coverage Test
  h=1 h=3 h=6 h=9 h=12
Model Better 0 0 1 0 1
RW Better 0 0 0 0 1

Note: In this panel, a better model is the one with more accurate empirical coverages. RW is the abbreviation of Random Walk.

Table 6.-Panel 3:  Results of Monetary Model, Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 7 6 8 9 9
RW Better 1 1 0 0 0

Note: In this panel, a better model is the one with tighter forecast intervals given equal coverage accuracy.

Table 6.-Panel 4:  Results of Monetary Model, Coverage Test and Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 7 6 9 9 10
RW Better 1 1 0 0 1

Note: In this panel, a better model is the one with either more accurate coverages or tighter forecast intervals given equal coverage accuracy.

Table 7.-Panel 1:  Results of Heterogenous Taylor Rules
 Cov. h=1 Leng. h=1 Cov. h=3 Leng. h=3 Cov. h=6 Leng. h=6 Cov. h=9 Leng. h=9 Cov. h=12 Leng. h=12

Australian Dollar

 0.915  7.155  0.909  14.690c 0.959  20.547  0.963y 26.364  0.947  29.583c

Canadian Dollar

 0.825  3.526  0.794  6.525c  0.797  9.040c  0.787  10.370c 0.693  11.352c

Danish Kroner

 0.915  8.548c 0.929  17.930c 0.938  25.328c 0.890  30.504c 0.904  36.624c

French Franc

 0.912  8.864c 0.880  15.970c 0.845  20.693c 0.968  30.436c 0.714  22.789c

Deutschmark

 0.917  8.605c 0.907  18.356c 0.894  28.121c 0.911c 31.378c 0.939  33.779c

Italian Lira

 0.913  8.659c 0.890  18.664  0.887  25.840c 0.831  32.037c 0.693  32.236c

Japanese Yen

 0.920  9.637z 0.888  19.352b 0.871  28.018c 0.932  33.388c 0.878  36.859c

Dutch Guilder

 0.936  8.851  0.916  18.822c 0.942  27.259c 0.970  31.410c 0.990  39.882c

Portuguese Escudo

 0.916  8.881z 0.870  17.651  0.758  18.730c 0.746  23.852c 0.600  20.593c

Swedish Krona

 0.828  7.428c 0.854  15.658c 0.903  24.315c 0.861  29.866c 0.876  36.235c

Swiss Franc

 0.935  9.731c 0.940  19.797  0.970  27.227c 0.969  32.179c 0.937  36.567c

British Pound

 0.919  8.350  0.908  16.774c 0.828  20.811c 0.783  23.105c 0.720  23.286c

Note: –h denotes forecast horizons for monthly data. –For each horizon (h), the first column (Cov.) reports empirical coverages given a nominal coverage of 90%. The second column (Leng.) reports the length of forecast intervals in terms of percentage change of the exchange rate. Empirical coverages and lengths are averages across N(h) out-of-sample trials. –Superscripts a, b, c in the column of Cov. (Leng.) denote rejections of equal coverage accuracy (equal length) in favor of the economic model at a 10%, 5% and 1% confidence level respectively. Superscripts x, y, z are defined analogously for rejections in favor of the random walk.

Table 7.-Panel 2:  Results of Heterogenous Taylor Rules, Coverage Test
  h=1 h=3 h=6 h=9 h=12
Model Better 0 0 0 1 0
RW Better 0 0 0 1 0

Note: In this panel, a better model is the one with more accurate empirical coverages. RW is the abbreviation of Random Walk.

Table 7.-Panel 3:  Results of Heterogenous Taylor Rules, Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 6 9 11 10 12
RW Better 2 0 0 0 0

Note: In this panel, a better model is the one with tighter forecast intervals given equal coverage accuracy.

Table 7.-Panel 4:  Results of Heterogenous Taylor Rules, Coverage Test and Length Test Given Equal Coverage Accuracy
  h=1 h=3 h=6 h=9 h=12
Model Better 6 9 11 11 12
RW Better 2 0 0 1 0

Note: In this panel, a better model is the one with either more accurate coverages or tighter forecast intervals given equal coverage accuracy.

Figure 1a.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (British Pound), 1-Month-Ahead Forecast

Data for Figure 1a mmediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 1a

DateTaylor RuleRW
1989M121.00001.0190
1990M10.98481.0019
1990M20.95430.9714
1990M30.92570.9448
1990M40.96950.9886
1990M50.96000.9810
1990M60.93900.9562
1990M70.92380.9390
1990M80.91240.8876
1990M90.87430.8495
1990M100.88380.8610
1990M110.84950.8305
1990M120.84000.8229
1991M10.86290.8400
1991M20.84950.8362
1991M30.84000.8229
1991M40.90860.8952
1991M50.94670.9314
1991M60.95240.9467
1991M71.00190.9905
1991M81.00190.9886
1991M90.98480.9695
1991M100.96760.9467
1991M110.97140.9467
1991M120.94860.9162
1992M10.91430.8933
1992M20.92570.9029
1992M30.93520.9181
1992M40.96380.9486
1992M50.94670.9295
1992M60.92570.9029
1992M70.90100.8800
1992M80.87430.8514
1992M90.86480.8400
1992M100.92000.8895
1992M111.01521.0190
1992M121.06481.1029
1993M11.08001.0857
1993M21.05901.0971
1993M31.14481.2019
1993M41.13141.1829
1993M51.07811.1314
1993M61.07431.0971
1993M71.10291.1257
1993M81.09141.1352
1993M91.09331.1390
1993M101.08951.1143
1993M111.08951.1314
1993M121.10481.1486
1994M11.09711.1390
1994M21.10101.1371
1994M31.10861.1486
1994M41.09901.1390
1994M51.10101.1467
1994M61.09901.1295
1994M71.08951.1124
1994M81.07811.0990
1994M91.05711.0914
1994M101.04191.0743
1994M111.03621.0476
1994M121.03241.0590
1995M11.04191.0800
1995M21.03621.0686
1995M31.03241.0705
1995M41.01331.0514
1995M51.03241.0476
1995M61.01711.0610
1995M71.01521.0533
1995M81.01711.0552
1995M91.03051.0743
1995M101.03811.0781
1995M111.03241.0648
1995M121.03241.0762
1996M11.04001.0933
1996M21.05521.1010
1996M31.04381.0876
1996M41.04951.0952
1996M51.03241.1029
1996M61.03241.1048
1996M71.04381.0857
1996M81.03811.0781
1996M91.03051.0781
1996M101.02481.0724
1996M111.01331.0533
1996M121.00191.0114
1997M10.99811.0114
1997M20.97331.0152
1997M30.99431.0362
1997M41.00381.0457
1997M50.99051.0324
1997M60.99811.0305
1997M70.99241.0229
1997M80.98101.0076
1997M91.03051.0476
1997M101.03241.0248
1997M111.01521.0038
1997M120.99620.9714
1998M11.00950.9886
1998M21.00950.9981
1998M30.99620.9924
1998M40.97900.9810
1998M50.96950.9752
1998M61.00950.9962
1998M71.00380.9886
1998M80.99810.9924
1998M91.00380.9981
1998M100.97710.9695
1998M110.96570.9619
1998M120.98480.9829
1999M10.97710.9752
1999M20.98670.9867
1999M30.99621.0019
1999M40.99621.0057
1999M51.00381.0133
1999M60.99621.0095
1999M71.01141.0229
1999M81.02861.0343
1999M91.00001.0152
1999M100.98861.0038
1999M110.97520.9848
1999M120.99241.0057
2000M10.99621.0114
2000M20.98670.9943
2000M31.00761.0190
2000M41.02101.0324
2000M51.01141.0305
2000M61.06101.0819
2000M71.06671.0819
2000M81.07051.0838
2000M91.07811.0971
2000M101.12191.1390
2000M111.11051.1257
2000M121.12191.1467
2001M11.09141.1162
2001M21.08191.1067
2001M31.09901.1257
2001M41.08761.1295
2001M51.08761.1371
2001M61.09521.1429
2001M71.11241.1638
2001M81.08571.1429
2001M91.06101.1105
2001M101.05331.0914
2001M111.06101.1010
2001M121.01331.1067
2002M11.00191.1029
2002M21.01331.1086
2002M31.00571.1143
2002M41.00381.1143
2002M50.99051.0990
2002M60.97521.0648
2002M70.96191.0476
2002M80.98671.0190
2002M91.00001.0343
2002M100.98671.0210
2002M110.98861.0210
2002M120.97711.0095
2003M10.96761.0000
2003M20.95810.9810
2003M30.96190.9886
2003M40.98291.0038
2003M50.98291.0095
2003M60.93140.9790
2003M70.91240.9543
2003M80.92570.9790
2003M90.94860.9752
2003M100.93520.9600
2003M110.90860.9181
2003M120.90480.9124
2004M10.89900.8800
2004M20.88570.8495
2004M30.85330.8324
2004M40.86860.8514
2004M50.87620.8629
2004M60.87240.8705
2004M70.85520.8438
2004M80.84760.8362
2004M90.85900.8476
2004M100.87050.8610
2004M110.84380.8229
2004M120.84380.8000
2005M10.82670.7733
2005M20.84190.7848
2005M30.83430.7714
2005M40.82670.7638
2005M50.82670.7676
2005M60.84190.7848
2005M70.85140.8000
2005M80.87240.8305
2005M90.84380.8095
2005M100.84000.8057
2005M110.85520.8229
2005M120.86670.8362
2006M10.84190.8305
2006M20.84000.7943
2006M30.83050.7905
2006M40.83240.7924

Figure 1b.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (British Pound), 6-month-ahead forecast

Data for Figure 1b immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 1b

DateTaylor RuleRW
1990M51.00001.0687
1990M60.98041.0528
1990M70.94421.0184
1990M80.92820.9914
1990M90.95151.0350
1990M100.99021.0270
1990M110.93681.0018
1990M120.90800.9822
1991M10.85640.9288
1991M20.85830.8840
1991M30.86500.9000
1991M40.85090.8730
1991M50.84790.8933
1991M60.85400.9135
1991M70.83620.9074
1991M80.83370.8939
1991M90.89200.9638
1991M100.94971.0031
1991M110.95091.0184
1991M121.01041.0656
1992M11.02271.0798
1992M20.98961.0595
1992M30.97851.0331
1992M40.97611.0350
1992M50.94291.0031
1992M60.92390.9767
1992M70.93680.9859
1992M80.94601.0037
1992M90.97791.0350
1992M100.97121.0153
1992M110.95770.9859
1992M120.93620.9613
1993M10.90250.9301
1993M20.88830.9178
1993M30.91350.9663
1993M40.99391.0798
1993M51.05461.1724
1993M61.04601.1736
1993M71.05771.1890
1993M81.08771.2840
1993M91.06561.2908
1993M101.00311.2209
1993M111.01601.2184
1993M121.04421.2503
1994M11.04601.2613
1994M21.03991.2650
1994M31.00861.2374
1994M41.03011.2558
1994M51.03131.2736
1994M61.02091.2644
1994M71.03191.2638
1994M81.02521.2755
1994M91.02701.2644
1994M101.01351.2724
1994M111.01231.2540
1994M121.02151.2362
1995M11.01291.2190
1995M21.00181.2233
1995M30.98591.2049
1995M40.96691.1742
1995M50.95951.1871
1995M60.96931.2098
1995M70.98961.1982
1995M80.98161.2000
1995M90.96871.1785
1995M100.94911.1736
1995M110.96561.1883
1995M120.96931.1828
1996M10.96931.1822
1996M20.97851.2037
1996M30.97611.2098
1996M40.97301.1951
1996M50.96131.2074
1996M60.96131.2245
1996M70.98711.2337
1996M80.96931.2276
1996M90.97361.2350
1996M100.97851.2442
1996M110.98341.2448
1996M120.97981.2239
1997M10.98341.2147
1997M20.96381.2166
1997M30.95831.2098
1997M40.93561.1896
1997M50.90671.1350
1997M60.90001.1337
1997M70.89691.1374
1997M80.91291.1601
1997M90.92941.1724
1997M100.91901.1577
1997M110.92331.1558
1997M120.93191.1466
1998M10.92091.1294
1998M20.95831.1528
1998M30.97301.1380
1998M40.96381.1147
1998M50.93931.0601
1998M60.93991.0748
1998M70.97241.0914
1998M80.95951.0871
1998M90.94601.0736
1998M100.92881.0669
1998M110.97061.0890
1998M120.95891.0810
1999M10.94601.0853
1999M20.96561.0920
1999M30.93371.0601
1999M40.94661.0528
1999M50.95211.0742
1999M60.94601.0675
1999M70.96691.0810
1999M80.95401.0963
1999M90.94661.1006
1999M100.95281.1086
1999M110.93681.1043
1999M120.94171.1184
2000M10.96071.1325
2000M20.92881.1110
2000M30.91471.0982
2000M40.90921.0761
2000M50.92091.1012
2000M60.93561.1061
2000M70.93741.0871
2000M80.93311.1153
2000M90.94111.1294
2000M100.92701.1276
2000M110.96871.1822
2000M120.97731.1822
2001M10.98281.1834
2001M20.96691.1982
2001M31.03561.2448
2001M40.98341.2294
2001M50.97481.2515
2001M60.93251.2190
2001M70.92021.2061
2001M80.88401.2270
2001M90.83681.1258
2001M100.84171.0356
2001M110.82941.0221
2001M120.83011.0399
2002M10.82941.0307
2002M20.80181.0147
2002M30.80370.9571
2002M40.80310.9613
2002M50.81410.9638
2002M60.80610.9454
2002M70.81470.9491
2002M80.81660.9485
2002M90.81720.9485
2002M100.80430.9356
2002M110.79450.9245
2002M120.80800.9092
2003M10.78100.8669
2003M20.77980.8779
2003M30.76440.8675
2003M40.77480.8663
2003M50.78160.8589
2003M60.75030.8503
2003M70.74290.8344
2003M80.72390.8393
2003M90.73620.8528
2003M100.71960.8571
2003M110.72760.8313
2003M120.72520.8074
2004M10.73190.8129
2004M20.73930.8055
2004M30.72880.7945
2004M40.71170.7644
2004M50.71100.7595
2004M60.70920.7325
2004M70.70740.7221
2004M80.71900.7055
2004M90.70670.7221
2004M100.71230.7307
2004M110.73190.7184
2004M120.72940.6736
2005M10.72820.6669
2005M20.73440.6761
2005M30.73990.6865
2005M40.74360.6804
2005M50.71900.6613
2005M60.69450.6380
2005M70.73130.6546
2005M80.72210.6521
2005M90.72150.6466
2005M100.72150.6491
2005M110.72880.6632
2005M120.73190.6773
2006M10.76320.7031
2006M20.73870.6521
2006M30.73930.6472
2006M40.68710.6626

Figure 1c.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (British Pound), 12-month-ahead forecast

Data for Figure 1c immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 1c

DateTaylor RuleRW
1990M111.00001.1366
1990M120.96681.1196
1991M10.86471.0826
1991M20.81361.0540
1991M30.89871.1005
1991M40.90661.0917
1991M50.76591.0656
1991M60.67501.0448
1991M70.63640.9875
1991M80.87880.9402
1991M90.75720.9510
1991M100.86720.9402
1991M110.84060.9415
1991M120.87800.9622
1992M10.85890.9560
1992M20.87090.9419
1992M30.69451.0154
1992M40.67831.0569
1992M50.67331.0731
1992M60.75971.1208
1992M70.75471.1200
1992M80.69491.0984
1992M90.69321.0714
1992M100.68491.0735
1992M110.67951.0394
1992M120.61480.9938
1993M10.61770.9983
1993M20.65341.0029
1993M30.68331.0345
1993M40.64591.0149
1993M50.65130.9855
1993M60.66130.9577
1993M70.60810.9116
1993M80.59940.8991
1993M90.60940.9465
1993M100.70731.0573
1993M110.84471.1445
1993M120.78661.1266
1994M10.86431.1403
1994M20.92901.2138
1994M30.92611.1955
1994M40.84181.1312
1994M50.82771.1287
1994M60.87381.1586
1994M70.87381.1876
1994M80.87261.2171
1994M90.84231.1905
1994M100.87711.2084
1994M110.88711.2262
1994M120.87511.2171
1995M10.88291.2163
1995M20.90411.2275
1995M30.87341.2167
1995M40.86051.2246
1995M50.84181.2067
1995M60.84391.1897
1995M70.81491.1739
1995M80.80571.1773
1995M90.74101.1594
1995M100.71401.1299
1995M110.73231.1424
1995M120.74301.1648
1996M10.77331.1532
1996M20.75431.1548
1996M30.74011.1345
1996M40.72351.1295
1996M50.73521.1436
1996M60.73721.1386
1996M70.70201.1378
1996M80.73021.1590
1996M90.72601.1644
1996M100.69741.1507
1996M110.69661.1615
1996M120.71941.1781
1997M10.79541.1876
1997M20.75221.1818
1997M30.76301.1889
1997M40.79241.1972
1997M50.79541.1980
1997M60.74931.1777
1997M70.75301.1689
1997M80.75341.1714
1997M90.70781.1640
1997M100.68121.1445
1997M110.68781.0922
1997M120.68041.0909
1998M10.68081.0946
1998M20.68701.1171
1998M30.70491.1034
1998M40.69571.0722
1998M50.69951.0565
1998M60.70491.0448
1998M70.68951.0232
1998M80.68371.0589
1998M90.69661.0544
1998M100.71771.0328
1998M110.73020.9597
1998M120.73270.9751
1999M10.68950.9900
1999M20.68160.9863
1999M30.71650.9738
1999M40.71940.9676
1999M50.70360.9880
1999M60.71190.9805
1999M70.69200.9851
1999M80.70940.9905
1999M90.73970.9622
1999M100.73520.9552
1999M110.71690.9689
1999M120.67120.9635
2000M10.66420.9755
2000M20.61890.9892
2000M30.63300.9929
2000M40.59361.0004
2000M50.59730.9967
2000M60.58451.0091
2000M70.60271.0216
2000M80.57951.0025
2000M90.60980.9905
2000M100.58780.9714
2000M110.58320.9929
2000M120.55750.9975
2001M10.55460.9813
2001M20.57121.0062
2001M30.56371.0191
2001M40.53131.0170
2001M50.53671.0668
2001M60.53631.0191
2001M70.53300.9896
2001M80.52970.9988
2001M90.51601.0340
2001M100.50770.9963
2001M110.49481.0029
2001M120.50810.9780
2002M10.50060.9676
2002M20.47360.9846
2002M30.47450.9900
2002M40.45870.9971
2002M50.46531.0025
2002M60.46201.0203
2002M70.45701.0108
2002M80.46200.9809
2002M90.47410.9498
2002M100.46530.9435
2002M110.46620.9527
2002M120.46330.9411
2003M10.46660.9170
2003M20.46080.9103
2003M30.46080.9103
2003M40.47280.8979
2003M50.47360.8871
2003M60.46330.8730
2003M70.50350.8323
2003M80.49810.8427
2003M90.54300.8323
2003M100.55750.8315
2003M110.56870.8248
2003M120.57990.8165
2004M10.57700.8007
2004M20.58200.8057
2004M30.56450.8186
2004M40.56870.8227
2004M50.58900.7983
2004M60.61020.7796
2004M70.59070.7792
2004M80.57580.7862
2004M90.57530.7684
2004M100.63510.7389
2004M110.59530.7347
2004M120.61850.7082
2005M10.53670.6800
2005M20.47200.6712
2005M30.53300.6866
2005M40.60400.6953
2005M50.61980.7020
2005M60.60400.6858
2005M70.53510.6800
2005M80.61100.6887
2005M90.61730.6990
2005M100.62100.6932
2005M110.53720.6737
2005M120.46700.6501
2006M10.63590.6671
2006M20.62140.6646
2006M30.64300.6584
2006M40.62600.6613

Figure 2a. Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (Deutschmark), 1-month-ahead forecast

Data for Figure 2a immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 2a

DateTaylor RuleRW
1989M121.00001.1060
1990M11.04711.0497
1990M20.95221.0190
1990M30.91560.9614
1990M40.95940.9777
1990M50.93850.9673
1990M60.90450.9535
1990M70.86780.9627
1990M80.83440.9372
1990M90.77290.8920
1990M100.77230.8920
1990M110.75200.8658
1990M120.71600.8442
1991M10.72120.8514
1991M20.61850.8580
1991M30.61980.8416
1991M40.86910.9228
1991M51.05760.9771
1991M60.97970.9869
1991M71.05691.0229
1991M81.00981.0242
1991M90.93261.0000
1991M100.90250.9719
1991M110.97320.9686
1991M121.03080.9300
1992M11.03660.8966
1992M21.04060.9058
1992M31.03010.9260
1992M40.95090.9509
1992M50.88220.9437
1992M60.86650.9287
1992M70.82660.8999
1992M80.86060.8966
1992M90.93260.8698
1992M100.83380.8724
1992M110.83840.8927
1992M120.91950.9562
1993M10.90050.9529
1993M20.91160.9725
1993M30.91880.9889
1993M40.91820.9915
1993M50.89400.9620
1993M60.89860.9679
1993M70.92600.9967
1993M80.98491.0334
1993M90.94111.0203
1993M100.90180.9764
1993M110.91100.9882
1993M120.94831.0242
1994M10.95681.0308
1994M20.99741.0497
1994M30.97121.0452
1994M40.94241.0183
1994M50.94831.0236
1994M60.92740.9980
1994M70.90840.9804
1994M80.87830.9437
1994M90.87630.9424
1994M100.86450.9332
1994M110.85470.9149
1994M120.86390.9274
1995M10.88150.9470
1995M20.85010.9215
1995M30.83700.9045
1995M40.84030.8495
1995M50.82530.8344
1995M60.73170.8488
1995M70.72510.8436
1995M80.70160.8364
1995M90.74930.8711
1995M100.78530.8796
1995M110.72380.8514
1995M120.72640.8541
1996M10.74870.8678
1996M20.78530.8815
1996M30.76240.8835
1996M40.79450.8901
1996M50.81090.9064
1996M60.82660.9234
1996M70.80430.9208
1996M80.79190.9045
1996M90.78010.8927
1996M100.79250.9084
1996M110.78730.9182
1996M120.78080.9084
1997M10.77880.9332
1997M20.82400.9640
1997M30.90771.0085
1997M40.94241.0209
1997M50.96071.0314
1997M60.94501.0268
1997M70.96011.0406
1997M80.99741.0805
1997M91.04451.1086
1997M100.98231.0687
1997M110.96601.0510
1997M120.95621.0360
1998M10.93851.0615
1998M20.94761.0838
1998M30.94631.0818
1998M41.00921.0903
1998M50.92021.0164
1998M60.90120.9954
1998M70.91161.0052
1998M80.93781.0085
1998M90.90381.0020
1998M100.86711.0013
1998M110.83250.9653
1998M120.86130.9921

 

Figure 2b.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (Deutschmark), 6-month-ahead forecast

Data for Figure 2b immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 2b

DateTaylor RuleRW
1990M51.00001.0091
1990M60.96140.9553
1990M70.90590.9300
1990M80.92350.9212
1990M90.91100.9171
1990M100.88220.9070
1990M110.84910.8944
1990M120.82960.9053
1991M10.81840.8807
1991M20.77470.8444
1991M30.77770.8446
1991M40.78440.8196
1991M50.73380.7991
1991M60.76510.8058
1991M70.75310.8116
1991M80.76470.7963
1991M90.78930.8671
1991M100.86100.9158
1991M110.92140.9457
1991M120.97141.0032
1992M11.04901.0085
1992M20.94061.0121
1992M30.91100.9830
1992M41.02570.9807
1992M50.90630.9409
1992M60.87490.9072
1992M70.90170.9165
1992M80.91140.9396
1992M90.91500.9644
1992M100.93540.9576
1992M110.91310.9419
1992M120.88130.9129
1993M10.85520.8656
1993M20.80820.8402
1993M30.80080.8425
1993M40.82850.8622
1993M50.90530.9216
1993M60.90340.9184
1993M70.98200.9371
1993M80.96500.9527
1993M90.93920.9559
1993M100.92520.9267
1993M110.92390.9328
1993M120.96190.9604
1994M11.00930.9960
1994M20.95210.9835
1994M30.91610.9415
1994M40.92010.9523
1994M50.97460.9871
1994M60.98660.9930
1994M71.01681.0115
1994M81.00401.0076
1994M90.95190.9816
1994M100.95850.9860
1994M110.95060.9616
1994M120.90270.9445
1995M10.89360.9099
1995M20.88560.9082
1995M30.86180.8993
1995M40.86030.8821
1995M50.87620.8938
1995M60.89170.9123
1995M70.87300.8883
1995M80.85460.8720
1995M90.79310.8162
1995M100.78270.8018
1995M110.79500.8183
1995M120.79590.8135
1996M10.79740.8061
1996M20.81920.8393
1996M30.82340.8476
1996M40.80060.8209
1996M50.81450.8228
1996M60.83260.8364
1996M70.81900.8497
1996M80.83640.8516
1996M90.82240.8576
1996M100.83510.8733
1996M110.85350.8896
1996M120.85480.8870
1997M10.84230.8722
1997M20.82430.8607
1997M30.83190.8754
1997M40.84490.8868
1997M50.83360.8777
1997M60.86140.9012
1997M70.89060.9315
1997M80.91920.9722
1997M90.91880.9835
1997M100.93000.9671
1997M110.95680.9593
1997M120.94320.9292
1998M10.95990.9307
1998M20.94170.9527
1998M30.88510.9220
1998M40.86460.8953
1998M50.86430.8826
1998M60.88960.9061
1998M70.89000.9254
1998M80.89300.9233
1998M90.88770.9309
1998M100.89040.9237
1998M110.88090.9044
1998M120.88000.9135

Figure 2c.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (Deutschmark), 12-month-ahead forecast

Data for Figure 2c immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 2c

DateTaylor RuleRW
1990M111.00001.0730
1990M120.96301.0191
1991M10.92600.9919
1991M20.93360.9827
1991M30.93190.9999
1991M40.94770.9887
1991M50.92770.9752
1991M60.91950.9870
1991M70.89440.9604
1991M80.85080.9207
1991M90.84570.9206
1991M100.84090.8935
1991M110.78620.8712
1991M120.80840.8786
1992M10.79190.8850
1992M20.78520.8681
1992M30.83350.9454
1992M40.88280.9985
1992M50.89461.0087
1992M60.92131.0455
1992M70.96761.0467
1992M80.91701.0223
1992M90.91050.9929
1992M100.95060.9905
1992M110.89250.9505
1992M120.86650.9166
1993M10.88120.9259
1993M20.89870.9492
1993M30.91360.9743
1993M40.92050.9672
1993M50.90480.9514
1993M60.88140.9221
1993M70.85460.8745
1993M80.82380.8487
1993M90.81800.8511
1993M100.84250.8708
1993M110.90150.9311
1993M120.90330.9277
1994M10.94250.9467
1994M20.94670.9625
1994M30.94240.9655
1994M40.92480.9362
1994M50.92600.9424
1994M60.95380.9703
1994M70.98531.0060
1994M80.95480.9936
1994M90.92350.9510
1994M100.93220.9619
1994M110.96800.9971
1994M120.97501.0031
1995M10.99791.0219
1995M20.99181.0177
1995M30.96190.9915
1995M40.96750.9960
1995M50.95830.9714
1995M60.93690.9541
1995M70.91520.9192
1995M80.91450.9174
1995M90.89270.9085
1995M100.88670.8912
1995M110.89510.9029
1995M120.91380.9216
1996M10.89840.8973
1996M20.88640.8808
1996M30.84690.8246
1996M40.85430.8099
1996M50.85810.8265
1996M60.85850.8217
1996M70.85010.8143
1996M80.88570.8476
1996M90.88920.8561
1996M100.87890.8293
1996M110.87520.8311
1996M120.88250.8448
1997M10.89140.8582
1997M20.89590.8602
1997M30.90190.8665
1997M40.91770.8821
1997M50.91710.8985
1997M60.92120.8962
1997M70.91880.8810
1997M80.90550.8694
1997M90.91250.8843
1997M100.92060.8913
1997M110.90760.8821
1997M120.91280.9058
1998M10.93470.9231
1998M20.96010.9595
1998M30.94600.9533
1998M40.93590.9365
1998M50.92370.9295
1998M60.90660.9366
1998M70.93470.9725
1998M80.99401.0035
1998M90.94950.9771
1998M100.93500.9615
1998M110.93320.9477
1998M120.94560.9731

Figure 3a.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (Japanese Yen), 1-month-ahead forecast

Data for Figure 3a immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 3a

DateTaylor ruleRW
1989M121.00000.9695
1990M10.99910.9706
1990M21.00870.9793
1990M31.00610.9841
1990M41.06951.0666
1990M51.10491.1024
1990M61.07531.0716
1990M71.07101.0382
1990M81.03401.0067
1990M91.04950.9950
1990M100.98580.9510
1990M110.99250.8902
1990M120.99300.8877
1991M11.03460.9197
1991M21.03050.9185
1991M31.00020.8968
1991M41.09980.9448
1991M51.09700.9429
1991M61.10970.9505
1991M71.10780.9611
1991M81.08860.9478
1991M91.07840.9409
1991M100.97800.9236
1991M110.95290.8993
1991M120.94620.8915
1992M10.93730.8805
1992M20.91580.8628
1992M30.91610.8782
1992M40.95020.9137
1992M50.95070.9184
1992M60.93470.8993
1992M70.90940.8723
1992M80.90300.8657
1992M90.90270.8681
1992M100.87470.8431
1992M110.86610.8333
1992M120.88440.8519
1993M10.88700.8530
1993M20.89510.8595
1993M30.86400.8305
1993M40.81600.8047
1993M50.77330.7731
1993M60.75990.7588
1993M70.65710.7387
1993M80.64140.7406
1993M90.61160.7136
1993M100.62990.7260
1993M110.63880.7360
1993M120.66510.7419
1994M10.74320.7559
1994M20.77070.7664
1994M30.66530.7311
1994M40.64190.7228
1994M50.62230.7117
1994M60.63670.7135
1994M70.62870.7051
1994M80.57320.6770
1994M90.57880.6873
1994M100.54370.6792
1994M110.50760.6763
1994M120.50750.6742
1995M10.57650.6890
1995M20.55520.6861
1995M30.51730.6636
1995M40.49770.6115
1995M50.60960.5772
1995M60.61990.5870
1995M70.61660.5832
1995M80.69070.6022
1995M90.78350.6534
1995M100.70010.7139
1995M110.70310.7159
1995M120.70410.7031
1996M10.70200.7025
1996M20.72080.7294
1996M30.72210.7297
1996M40.72300.7307
1996M50.73890.7394
1996M60.72290.7334
1996M70.74090.7507
1996M80.73940.7523
1996M90.72950.7432
1996M100.74600.7574
1996M110.76860.7745
1996M120.77080.7738
1997M10.78380.7690
1997M20.81100.7955
1997M30.85990.8306
1997M40.85800.8293
1997M50.87190.8486
1997M60.83000.8051
1997M70.78430.7720
1997M80.79360.7793
1997M90.80980.7966
1997M100.82720.8166
1997M110.83040.8177
1997M120.86320.8469
1998M10.90770.8763
1998M20.90620.8751
1998M30.86110.8501
1998M40.88240.8719
1998M50.90430.8899
1998M60.92800.9112
1998M70.97610.9479
1998M80.97360.9510
1998M90.99490.9773
1998M100.98420.9265
1998M110.83840.8431
1998M120.82100.8378
1999M10.79270.8154
1999M20.76440.7874
1999M30.79040.8108
1999M40.81140.8303
1999M50.81290.8324
1999M60.83030.8478
1999M70.84640.8390
1999M80.82240.8204
1999M90.76000.7784
1999M100.70400.7406
1999M110.69170.7343
1999M120.66710.7251
2000M10.64970.7108
2000M20.67010.7296
2000M30.72600.7580
2000M40.70840.7367
2000M50.68060.7319
2000M60.71850.7506
2000M70.70780.7354
2000M80.71870.7498
2000M90.71190.7489
2000M100.71000.7403
2000M110.71710.7514
2000M120.72090.7553
2001M10.74290.7775
2001M20.82220.8084
2001M30.80690.8045
2001M40.88090.8420
2001M50.89240.8576
2001M60.88570.8437
2001M70.89060.8478
2001M80.94350.8627
2001M90.88300.8410
2001M100.85470.8218
2001M110.88770.8415
2001M120.89990.8482
2002M10.95440.8869
2002M21.03580.9223
2002M31.04900.9290
2002M41.01520.9111
2002M51.01110.9090
2002M60.96120.8717
2002M70.89950.8503
2002M80.84900.8132
2002M90.85440.8207
2002M100.86440.8179
2002M110.89080.8370
2002M120.86470.8214
2003M10.86510.8233
2003M20.84930.8025
2003M30.83720.8021
2003M40.82650.7977
2003M50.82930.8058
2003M60.81530.7888
2003M70.82730.7926
2003M80.82980.7951
2003M90.82900.7948
2003M100.79120.7690
2003M110.75330.7334
2003M120.71200.7194
2004M10.66620.7099
2004M20.66290.7003
2004M30.70010.7031
2004M40.67520.7150
2004M50.66820.7094
2004M60.69810.7536
2004M70.67760.7335
2004M80.64530.6950
2004M90.64780.6997
2004M100.64510.6988
2004M110.63820.6905
2004M120.61800.6646
2005M10.61250.6590
2005M20.61120.6559
2005M30.62320.6528
2005M40.62260.6547
2005M50.63310.6668
2005M60.62210.6631
2005M70.63730.6765
2005M80.65460.6964
2005M90.64830.6880
2005M100.65440.6920
2005M110.66160.7145
2005M120.67500.7368
2006M10.66030.7360
2006M20.62010.7140
2006M30.62670.7287
2006M40.62380.7252
2006M50.62640.7239
2006M60.67030.6908

Figure 3b.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (Japanese Yen), 6-month-ahead forecast

Data for Figure 3b immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 3b

DateTaylor RuleRW
1990M51.00001.0812
1990M60.98721.0825
1990M71.01201.0922
1990M81.02821.0975
1990M91.23111.1483
1990M101.29281.1869
1990M111.13661.1537
1990M121.15361.1512
1991M10.87901.1163
1991M20.85421.1045
1991M30.76771.0369
1991M40.70390.9940
1991M50.72920.9911
1991M60.85561.0269
1991M70.85091.0255
1991M80.77211.0012
1991M90.94071.0537
1991M100.87341.0516
1991M110.83301.0601
1991M120.92491.0719
1992M10.82681.0571
1992M20.81981.0494
1992M30.78341.0301
1992M40.70621.0029
1992M50.68960.9943
1992M60.68420.9820
1992M70.62960.9623
1992M80.69320.9795
1992M90.78361.0190
1992M100.78821.0242
1992M110.79331.0029
1992M120.72220.9728
1993M10.73940.9655
1993M20.76750.9682
1993M30.63090.9403
1993M40.74110.9294
1993M50.76270.9501
1993M60.75020.9514
1993M70.76160.9586
1993M80.67550.9262
1993M90.75270.8975
1993M100.68620.8622
1993M110.69720.8463
1993M120.66030.8239
1994M10.72950.8260
1994M20.71720.7959
1994M30.72540.8097
1994M40.75230.8208
1994M50.77510.8274
1994M60.78630.8430
1994M70.80500.8547
1994M80.63170.8153
1994M90.56490.8061
1994M100.55710.7937
1994M110.56470.7958
1994M120.52840.7864
1995M10.51200.7551
1995M20.53520.7665
1995M30.40090.7576
1995M40.31060.7366
1995M50.31050.7304
1995M60.45790.7431
1995M70.39740.7401
1995M80.34950.7287
1995M90.31290.6715
1995M100.37250.6208
1995M110.37670.6313
1995M120.40340.6239
1996M10.41880.6420
1996M20.48210.6954
1996M30.53110.7381
1996M40.64900.7407
1996M50.65470.7562
1996M60.65030.7599
1996M70.68800.7890
1996M80.69110.7893
1996M90.68450.7904
1996M100.68110.7952
1996M110.68590.7872
1996M120.69040.8067
1997M10.69210.8084
1997M20.67790.7986
1997M30.69130.8138
1997M40.69990.8322
1997M50.70180.8314
1997M60.71010.8438
1997M70.72270.8729
1997M80.75480.9174
1997M90.75290.9159
1997M100.79900.9374
1997M110.77430.8892
1997M120.73890.8527
1998M10.74810.8608
1998M20.76720.8799
1998M30.78260.8978
1998M40.78180.8966
1998M50.70190.9285
1998M60.67850.9634
1998M70.74180.9666
1998M80.74060.9389
1998M90.72970.9630
1998M100.79450.9829
1998M110.77271.0064
1998M120.85491.0470
1999M10.89921.0504
1999M21.21641.0794
1999M31.00590.9987
1999M40.86640.8989
1999M50.87220.8933
1999M60.85550.8694
1999M70.75130.8496
1999M80.85700.8978
1999M90.90230.9194
1999M100.90260.9217
1999M110.92750.9388
1999M120.92120.9290
2000M10.78950.9183
2000M20.71290.8713
2000M30.68270.8225
2000M40.67320.8155
2000M50.66600.8053
2000M60.64430.7894
2000M70.65570.8103
2000M80.66930.8418
2000M90.65860.8181
2000M100.65520.8128
2000M110.66620.8336
2000M120.67070.8167
2001M10.68450.8327
2001M20.68730.8317
2001M30.66500.8221
2001M40.68600.8345
2001M50.68020.8388
2001M60.70100.8635
2001M70.72590.8978
2001M80.74440.8945
2001M90.77900.9393
2001M100.80580.9692
2001M110.79010.9535
2001M120.78650.9581
2002M10.80840.9749
2002M20.76910.9504
2002M30.75460.9288
2002M40.76370.9510
2002M50.77950.9586
2002M60.80070.9991
2002M70.85701.0128
2002M80.86341.0105
2002M90.91520.9737
2002M100.91820.9709
2002M110.87670.9234
2002M120.87200.8818
2003M10.79430.8289
2003M20.81240.8363
2003M30.79500.8471
2003M40.83490.8451
2003M50.82190.8293
2003M60.82800.8312
2003M70.79460.8102
2003M80.79860.8139
2003M90.79610.8094
2003M100.76870.8177
2003M110.74150.8004
2003M120.71710.8070
2004M10.72170.8095
2004M20.72400.8093
2004M30.70270.7829
2004M40.70500.7467
2004M50.67970.7446
2004M60.69380.7347
2004M70.65340.7247
2004M80.67660.7277
2004M90.65710.7357
2004M100.64740.7299
2004M110.65530.7607
2004M120.64100.7419
2005M10.64280.7423
2005M20.62770.7474
2005M30.62830.7464
2005M40.59760.7375
2005M50.57340.7099
2005M60.57080.7039
2005M70.56810.7006
2005M80.56490.7115
2005M90.54560.7136
2005M100.58900.7267
2005M110.58240.7228
2005M120.59300.7374
2006M10.61850.7591
2006M20.61350.7349
2006M30.61080.7391
2006M40.66720.7633
2006M50.70750.7871
2006M60.75700.7871

Figure 3c.  Length of Forecast Intervals for Benchmark Taylor Rule and Random Walk Models (Japanese Yen), 12-month-ahead forecast

Data for Figure 3c immediately follows

Note: To facilitate graphical comparisons, the 6- and 12-month-ahead forecast intervals of the random walk have been relocated such that they have the same center as the intervals of the Taylor rule model.

Data for Figure 3c

DateTaylor RuleRW
1990M111.00001.6165
1990M120.99011.6184
1991M11.18051.6329
1991M21.25771.6409
1991M31.43001.7498
1991M41.49121.8168
1991M51.43111.7661
1991M61.36021.7622
1991M71.14901.7088
1991M81.07861.6907
1991M90.96311.5872
1991M100.93541.4858
1991M111.00581.4815
1991M121.04881.5351
1992M10.89361.5329
1992M21.00131.4967
1992M30.91081.5752
1992M40.89651.5720
1992M50.88581.5847
1992M60.80411.6023
1992M70.77011.5802
1992M80.89931.5687
1992M90.90081.5398
1992M101.01231.4992
1992M111.00341.4863
1992M121.02021.4679
1993M10.95001.4384
1993M20.84991.4641
1993M30.95871.5233
1993M40.96061.5311
1993M51.00741.4992
1993M61.05631.4542
1993M71.08681.4432
1993M81.08651.4473
1993M91.03141.4056
1993M101.02721.3893
1993M111.05611.4203
1993M121.05051.4221
1994M11.00481.4330
1994M20.92231.3845
1994M30.90841.3416
1994M40.68621.2889
1994M50.53701.2651
1994M60.52971.2315
1994M70.53531.2347
1994M80.52191.1898
1994M90.53191.2104
1994M100.72221.2270
1994M110.74331.2368
1994M120.75891.2602
1995M10.91291.2777
1995M20.73511.2188
1995M30.70961.2050
1995M40.69671.1806
1995M50.70941.1607
1995M60.72121.1267
1995M70.65591.0818
1995M80.64511.0982
1995M90.57861.0853
1995M100.57881.0807
1995M110.55671.0773
1995M120.71311.1009
1996M10.66541.0964
1996M20.59641.0795
1996M30.27800.9947
1996M40.54060.9196
1996M50.56870.9352
1996M60.58340.9129
1996M70.35460.9374
1996M80.37701.0036
1996M90.76291.0609
1996M100.82001.0438
1996M110.87231.0489
1996M120.85931.0453
1997M10.92561.0854
1997M20.90181.0858
1997M30.86471.0900
1997M40.83241.1097
1997M50.85881.1219
1997M60.85601.1687
1997M70.84771.1777
1997M80.84871.1635
1997M90.80761.1857
1997M100.87921.2125
1997M110.88521.2113
1997M120.89061.2294
1998M10.91821.2718
1998M20.88761.3263
1998M30.88121.3242
1998M40.89281.3718
1998M50.91791.3014
1998M60.89111.2479
1998M70.89751.2598
1998M80.90381.2877
1998M90.89041.3200
1998M100.86061.3219
1998M110.82381.3689
1998M120.53441.4166
1999M10.84501.4146
1999M20.88701.3742
1999M30.83281.4094
1999M40.78421.4386
1999M50.81771.4729
1999M60.84361.5323
1999M70.84261.5373
1999M81.05421.5856
1999M90.86481.4738
1999M101.06211.3266
1999M110.89151.3183
1999M121.06231.2831
2000M11.05711.2417
2000M20.84771.2786
2000M30.84511.3094
2000M40.78531.3127
2000M50.79341.3370
2000M60.78211.3231
2000M70.76951.3078
2000M81.01031.2409
2000M90.92861.1713
2000M100.73291.1614
2000M110.72741.1469
2000M120.71531.1242
2001M10.72001.1540
2001M20.71691.1988
2001M30.71411.1651
2001M40.80481.1576
2001M50.72201.1871
2001M60.89761.1632
2001M70.83231.1860
2001M80.95161.1845
2001M90.71381.1709
2001M100.92141.1884
2001M110.93731.1946
2001M120.79691.2298
2002M10.69331.2786
2002M20.73061.2739
2002M30.61881.3317
2002M40.54801.3564
2002M50.54721.3345
2002M60.41401.3409
2002M70.36221.3644
2002M80.53461.3301
2002M90.59971.2998
2002M100.52111.1940
2002M110.36071.1789
2002M120.33311.2012
2003M10.33211.2379
2003M20.28741.2363
2003M30.81791.2090
2003M40.83811.1750
2003M50.83521.1125
2003M60.84841.0725
2003M70.89881.0203
2003M80.89801.0220
2003M90.85981.0378
2003M100.81901.0621
2003M110.83381.0423
2003M120.83991.0267
2004M10.89281.0008
2004M20.89351.0053
2004M30.88760.9998
2004M40.87561.0100
2004M50.90650.9886
2004M60.88990.9968
2004M70.82190.9763
2004M80.75250.9691
2004M90.77210.9371
2004M100.77950.8888
2004M110.74370.8780
2004M120.77260.8664
2005M10.72450.8546
2005M20.79960.8581
2005M30.71410.8726
2005M40.68930.8658
2005M50.52550.9023
2005M60.55790.8800
2005M70.53320.8804
2005M80.50970.8865
2005M90.50910.8853
2005M100.59450.8747
2005M110.67870.8420
2005M120.70250.8348
2006M10.67180.8310
2006M20.60960.8439
2006M30.53780.8463
2006M40.42470.8620
2006M50.46140.8573
2006M60.39450.8746

 

References

Berkowitz, J. and G. Lorenzo (2001) "Long-Horizon Exchange Rate Predictability?" The Review of Economics and Statistics 83(1), 81-91.

Boero, G. and E. Marrocu (2004) "The performance of SETAR models: a regime conditional evaluation of point, interval and density forecasts," International Journal of Forecasting 20(2), 305-320.

Chen, Y. and K. P. Tsang (2009) “What Does the Yield Curve Tell Us About Exchange Rate Predictability?” Manuscript, University of Washington, and Virginia Tech.

Cheung, Y., M. D. Chinn, and A. Pascual (2005) "Empirical Exchange Rate Models of the Nineties: Are Any Fit to Survive?" Journal of International Money and Finance 24, 1150-1175.

Chinn, M. D. (forthcoming) “Nonlinearities, Business Cycles and Exchange Rates,” Economics Notes.

Chinn, M. D. and R. A. Meese (1995) "Banking on Currency Forecasts: How Predictable Is Change in Money?" Journal of International Economics 38, 161-178.

Christoffersen, P. F. (1998) "Evaluating Interval Forecasts," International Economic Review 39(4), 841-862.

Christoffersen, P. F. and S. Mazzotta (2005) “The Accuracy of Density Forecasts from Foreign
Exchange Options,” Journal of Financial Econometrics 3(4), 578-605.

Clarida, R., Gali, J. and M. Gertler (1998) "Monetary Rules in Practice: Some International Evidence," European Economic Review 42, 1033-1067.

Clarida, R.H., L. Sarno, M. P. Taylor, and G. Valente (2003) "The Out-of-Sample Success of Term Structure Models as Exchange Rate Predictors: A Step Beyond," Journal of International Economics 60, 61-83.

Clark, T. and K. D. West (2006) "Using Out-of-Sample Mean Squared Prediction Errors to Test the Martingale Difference Hypothesis," Journal of Econometrics 135 (1-2), 155-186.

Clark, T. and K. D. West (2007) "Approximately Normal Tests for Equal Predictive Accuracy in Nested Models," Journal of Econometrics 138(1), 291-311.

Corradi, V. and N. Swanson (2006a) "Predictive Density and Conditional Confidence Interval Accuracy Tests," Journal of Econometrics 135, 187-228.

Corradi, V. and N. Swanson (2006b) "Predictive Density Evaluation," In Grangerm C.W.J., Elliott, G., Timmerman, A. (Eds.), Handbook of Economic Forecasting, Elsevier, Amsterdam.

Diebold, F. X., Gunther, T. A. and A. S. Tay (1998) "Evaluating Density Forecasts with Applications to Financial Risk Management," International Economic Review 39(4), 863-883.

Diebold, F. X., Hahn, J. and A .S. Tay (1999) "Multivariate Density Forecast Evaluation and Calibration in Financial Risk Management: High-Frequency Returns of Foreign Exchange," Review of Economics and Statistics 81, 661-673.

Diebold, F. X. and R. S. Mariano (1995) "Comparing Predictive Accuracy," Journal of Business and Economic Statistics 13, 253-263.

Engel, C., N. Mark, and K. West (2007) "Exchange Rate Models are Not as Bad as You Think," in NBER Macroeconomics Annual.

Engel, C. and K. West (2005) "Exchange Rates and Fundamentals," Journal of Political Economy 113, 485-517.

Engel, C. and K. D. West (2006) "Taylor Rules and the Deutschmark-Dollar Real Exchange Rate," Journal of Money, Credit and Banking 38(5), 1175-1194.

Engel, C., J. Wang, and J. J. Wu (2008) "Can Long-horizon Data Beat the Random Walk under the Engel-West Explanation?" Working Paper, University of Wisconsin-Madison, the Federal Reserve Bank of Dallas, and the Federal Reserve Board.

Faust, J., J. Rogers, and J. Wright, (2003) "Exchange Rate Forecasting: The Errors We've Really Made," Journal of International Economics 60, 35-59.

Giacomini, R. and H. White (2006) "Tests of Conditional Predictive Ability," Econometrica 74, 1545-1578.

Groen, J. J. (2000) "The Monetary Exchange Rate Model as a Long-Run Phenomenon," Journal of International Economics 52, 299-319.

Hall, P., R.C.L. Wolff, and Q. Yao (1999) "Methods for Estimating a Conditional Distribution Function," Journal of American Statistical Association 94, 154-163.

Hong, Y., H. Li, and F. Zhao (2007) "Can the Random Walk be Beaten in Out-of-Sample Density Forecasts: Evidence from Intraday Foreign Exchange Rates," Journal of Econometrics 141, 736-776.

J.P. Morgan (1996) RiskMetrics Technical Document.

Kilian, L. (1999) "Exchange Rates And Monetary Fundamentals: What Do We Learn From Long-Horizon Regressions?" Journal of Applied Econometrics 14, 491-510.

Kilian, L. and M. Taylor (2003) "Why Is It So Difficult to Beat the Random Walk Forecast of Exchange Rate?" Journal of International Economics 60, 85-107.

MacDonald, R. and M. P. Taylor (1994) "The Monetary Model of the Exchange Rate: Long-Run Relationships, Short-Run Dynamics, and How to Beat a Random Walk," Journal of International Money and Finance 13, 276-290.

Mark, N. C. (1995) "Exchange Rates and Fundamentals: Evidence on Long-Horizon Predictability,'' American Economic Review 85, 201-218.

Mark, N. C. (2007) "Changing Monetary Policy Rules, Learning, and Real Exchange Rate Dynamics," Manuscript, University of Notre Dame.

Mark, N. and D. Sul (2001) "Nominal Exchange Rates and Monetary Fundamentals Evidence from a Small Post-Bretton Woods Panel," Journal of International Economics 53, 29-52.

Meese, R. A. and K. Rogoff (1983) "Empirical Exchange Rate Models of the Seventies: Do they Fit Out-of-Sample?'' Journal of International Economics 14, 3-24.

Molodtsova, T. and D. H. Papell (2009) "Out-of-Sample Exchange Rate Predictability with Taylor Rule Fundamentals," Journal of International Economics, 77(2), 167-180.

Molodtsova, T., A. Nikolsko-Rzhevskyy, and D. H. Papell (2008a), "Taylor Rules with Real-Time Data: A Tale of Two Countries and One Exchange Rate," Journal of Monetary Economics 55, S63-S79.

Molodtsova, T., A. Nikolsko-Rzhevskyy, and D. H. Papell (2008b), “Taylor Rules and the
Euro,” Manuscript Emory University, University of Memphis, and University of Houston.

Nason, J. and J. Rogers (2008) "Exchange Rates and Fundamentals: A Generalization," International Finance Discussion Papers, Number 948, Board of Governors of the Federal Reserve System.

Newey, W. K. and K. D. West (1987) "A Simple, Positive Semi-definite, Heteroskedasticity and Autocorrelation Consistent Covariance Matrix" Econometrica 55, 703-708.

Rogoff, K. S. and V. Stavrakeva (2008) “The Continuing Puzzle of Short Horizon Exchange Rate
Forecasting,” NBER Working Paper No. 14071.

Rossi, B. (2005) "Testing Long-horizon Predictive Ability with High Persistence, and the Meese-Rogoff Puzzle," International Economic Review 46(1), 61-92.

Sarno, L. and G. Valente (2005) "Empirical Exchange Rate Models and Currency Risk: Some Evidence from Density Forecasts," Journal of International, Money and Finance 24(2), 363-385.

Sarno, L. and G. Valente (forthcoming) “Exchange Rates and Fundamentals: Footloose or Evolving
Relationship?” Journal of the European Economic Association.

West, K. D. (1996) "Asymptotic Inference About Predictive Ability," Econometrica 64, 1067-1084.

Wu, J. J. (2007) "Robust Semiparametric Forecast Intervals," Manuscript, the Federal Reserve Board.


APPENDIX

A.1  Monetary and Taylor Rule Models

In this section, we describe the monetary and Taylor rule models used in the paper.

A.1.1  Monetary Model

Assume the money market clearing condition in the home country is:
$\displaystyle m_t=p_t+\gamma y_t-\alpha i_t+v_t,$

where $ m_t$ is the log of money supply, $ p_t$ is the log of aggregate price, $ i_t$ is the nominal interest rate, $ y_t$ is the log of output, and $ v_t$ is the money demand shock. A symmetric condition holds in the foreign country and we use an asterisk in superscript to denote variables in the foreign country. Subtracting the foreign money market clearing condition from the home, we have:

$\displaystyle i_t-i_t^\ast=\frac{1}{\alpha}\left[-(m_t-m_t^\ast)+(p_t-p_t^\ast)+\gamma(y_t-y_t^\ast)+(v_t-v_t^\ast)\right].$ (A.1.1)

The nominal exchange rate is equal to its purchasing power value plus the real exchange rate:

$\displaystyle s_t=p_t-p_t^\ast+q_t.$ (A.1.2)

The uncovered interest rate parity in financial market takes the form:

$\displaystyle E_ts_{t+1}-s_t=i_t-i_t^\ast+\rho_t,$ (A.1.3)

where $ \rho_t$ is the uncovered interest rate parity shock. Substituting equations (A.1.1) and (A.1.2) into (A.1.3), we have

$\displaystyle s_t=(1-b)\left[m_t-m_t^\ast-\gamma(y_t-y_t^\ast)+q_t-(v_t-v_t^\ast)\right]-b\rho_t+bE_ts_{t+1},$ (A.1.4)

where $ b=\alpha/(1+\alpha)$. Solving $ s_t$ recursively and applying the "no-bubbles" condition, we have:

$\displaystyle s_t=E_t\left\{(1-b)\sum_{j=0}^\infty b^j\left[m_{t+j}-m_{t+1}^\ast-\gamma(y_{t+j}-y_{t+1}^\ast)+q_{t+1}-(v_{t+j}-v_{t+j}^\ast)\right]-b\sum_{j=1}^\infty b^{j}\rho_{t+j}\right\}.$ (A.1.5)

In the standard monetary model, such as Mark (1995), purchasing power parity ($ q_t=0$) and uncovered interest rate parity hold ($ \rho_t=0$). Furthermore, it is assumed that the money demand shock is zero ( $ v_t=v_t^\ast=0$) and $ \gamma=1$. Equation (A.1.5) reduces to:

$\displaystyle s_{t}=E_{t}\left\{(1-b)\sum_{j=0}^{\infty}b^{j}\left(m_{t+j}-m^{*}_{t+j}-(y_{t+j}-y^{*}_{t+j})\right)\right\}.$

A.1.2  Taylor Rule Model

We follow Engel and West (2005) to assume that both countries follow the Taylor rule and the foreign country targets the exchange rate in its Taylor rule. The interest rate differential is:

$\displaystyle i_t-i_t^\ast=\delta_s(s_t-\bar{s}_t^\ast)+\delta_y(y_t^{gap}-y_t^{gap\ast })+\delta_\pi(\pi_t-\pi_t^{\ast})+v_t-v_t^\ast,$ (A.1.6)

where $ \bar{s}_t^\ast$ is the targeted exchange rate. Assume that monetary authorities target the PPP level of the exchange rate: $ \bar{s}_t^\ast=p_t-p_t^\ast$. Substituting this condition and the interest rate differential into the UIP condition, we have:

$\displaystyle s_t=(1-b)(p_t-p_t^\ast)-b\left[\delta_y(y_t^{gap}-y_t^{gap\ast })+\delta_\pi(\pi_t-\pi_t^{\ast})+v_t-v_t^\ast\right]-b\rho_t+bE_ts_{t+1},$ (A.1.7)

where $ b=\frac{1}{1+\delta_s}$. Assuming that uncovered interest rate parity holds ($ \rho_t=0$) and monetary shocks are zero, equation (A.1.7) reduces to the benchmark Taylor rule model in our paper:

$\displaystyle s_{t}=E_{t}\left\{(1-b)\sum_{j=0}^{\infty}b^{j}(p_{t+j}-p^{*}_{t+j})-b\sum_{j=0}^{\infty}b^{j}(\delta_{y}(y^{gap}_{t+j}-y_{t+j}^{gap*})+\delta_{\pi}(\pi_{t+j}-\pi^{*}_{t+j}))\right\}.$

A.2  Long-horizon Regressions

In this section, we derive long-horizon regressions for the monetary model and the benchmark Taylor rule model.

A.2.1  Monetary Model

In the monetary model:

$\displaystyle s_{t}=E_{t}\left\{(1-b)\sum_{j=0}^{\infty}b^{j}\left(m_{t+j}-m^{*}_{t+j}-(y_{t+j}-y^{*}_{t+j})\right)\right\},$

where $ m_{t}$ and $ y_{t}$ are logarithms of domestic money stock and output, respectively. The superscript $ *$ denotes the foreign country. Money supplies ($ m_t$ and $ m_t^*$) and total outputs ($ y_t$ and $ y_t^*$) are usually I(1) variables. The general form considered in Engel, Wang, and Wu(2008) is:

$\displaystyle s_{t}$ $\displaystyle =$ $\displaystyle (1-b)\sum_{j=0}^{\infty}b^{j}E_{t}\alpha^{'}\mathbf{D}_{t}$  
$\displaystyle (I_{n}-\Phi(L))\Delta\mathbf{D}_{t}$ $\displaystyle =$ $\displaystyle \varepsilon_{t}$ (A.2.1)
$\displaystyle E(\varepsilon_{t+j}\vert\varepsilon_{t},\varepsilon_{t-1},...)$ $\displaystyle \equiv$ $\displaystyle E_{t}(\varepsilon_{t+j})=0, \forall j\ge 1,$  

where $ n$ is the dimension of $ \mathbf{D}_{t}$ and $ I_n$ is an $ n\times n$ identity matrix. $ L$ is the lag operator and $ \Phi(L)=\phi_{1}L+\phi_{2}L^{2}+...+\phi_{p}L^{p}$. Assume $ \Phi(1)$ is non-diagonal and the covariance matrix of $ \varepsilon_t$ is given by $ \Omega=E_t[\varepsilon_t\varepsilon_t']$. We assume that the change of fundamentals follows a VAR(p) process in our setup. From proposition 1 of Engel, Wang, Wu (2008), we know that for a fixed discount factor $ b$ and $ p\ge 2$,

$\displaystyle s_{t+h}-s_{t}=\beta_{h}z_{t}+\delta^{'}_{0,h}\Delta\mathbf{D}_{t}+...+\delta^{'}_{p-2,h}\Delta\mathbf{D}_{t-p+2}+\zeta_{t+h}$

is a correctly specified regression where the regressors and errors do not correlate. In the case of $ p=1$, the long-horizon regressions reduces to

$\displaystyle s_{t+h}-s_{t}=\beta_{h}z_{t}+\zeta_{t+h}.$

Following the literature, for instance Mark (1995), we do not include $ \Delta\mathbf{D}_{t}$ and its lags in our long-horizon regressions. The monetary model can be written in the form of (A.2.1) by setting $ \mathbf{D}_{t}=[m_{t}\quad m^{*}_{t}\quad y_{t}\quad y^{*}_{t}]'$ , $ \alpha=[1\quad -1\quad -1\quad 1]'$. By definition, $ z_{t}=s_{t}-(m_{t}-m^{*}_{t})+(y_{t}-y^{*}_{t})$. This corresponds to $ \beta_{m,h}=1$, $ \mathbf{X}_{m,t} =s_{t}-(m_{t}-m^{*}_{t})+(y_{t}-y^{*}_{t})$ in equation (1) of section 3.

A.2.2  Taylor Rule Model

In the Taylor rule model

$\displaystyle s_{t}=E_{t}\left\{(1-b)\sum_{j=0}^{\infty}b^{j}(p_{t+j}-p^{*}_{t+j})-b\sum_{j=0}^{\infty}b^{j}(\delta_{y}(y^{gap}_{t+j}-y_{t+j}^{gap*})+\delta_{\pi}(\pi_{t+j}-\pi^{*}_{t+j}))\right\},$

where $ p_{t}$, $ y^{gap}_{t}$ and $ \pi_{t}$ are domestic aggregate price, output gap and inflation rate, respectively. $ \delta_{y}$ and $ \delta_{\pi}$ are coefficients of the Taylor rule model. The aggregate prices $ p_t$ and $ p_t^\ast$ are usually I(1) variables. Inflation and output gap are more likely to be I(0). Engel, Wang, and Wu (2008) consider a setup which includes both stationary and non-stationary variables:

$\displaystyle s_t=(1-b)\sum_{j=0}^\infty b^jE_t\left[f_{1t+j}\right]$ $\displaystyle +b\sum_{j=0}^\infty b^jE_t\left[f_{2t+j}+u_{2t+j}\right]$  
$\displaystyle f_{1t}$ $\displaystyle =\alpha_1'\mathbf{D_t}\sim I(1)$    
$\displaystyle f_{2t}$ $\displaystyle =\alpha_2'\mathbf{\Delta D_t}\sim I(0)$    
$\displaystyle u_{2t}$ $\displaystyle =\alpha_3'\mathbf{\Delta D_t}\sim I(0)$    
$\displaystyle (I_{n}$ $\displaystyle -\Phi(L))\Delta\mathbf{X}_{t}=\varepsilon_{t},$ (A.2.2)

where $ f_{1t}$ and $ f_{2t}$ ($ u_{2t}$) are observable (unobservable) fundamentals. $ \Delta\mathbf{D}_{t}$ is the first difference of $ \mathbf{D}_{t}$, which contains I(1) economic variables.24From proposition 2 of Engel, Wang, and Wu (2008), we know that for a fixed discount factor $ b$ and $ h\ge 2$,

$\displaystyle s_{t+h}-s_{t}=\tilde{\beta}_{h}z_{t}+\sum_{k=0}^{p-1}\tilde{\delta}^{'}_{k,h}\Delta\mathbf{D}_{t-k}+\tilde{\zeta}_{t+h}$ (A.2.3)

is a correctly specified regression, where the regressors and errors do not correlate. In the case of $ p=1$, the long-horizon regressions reduces to:

$\displaystyle s_{t+h}-s_{t}=\tilde{\beta}_{h}z_{t}+\tilde{\zeta}_{t+h}.$

The Taylor rule model can be written into the form of (A.2.2) by setting

$\displaystyle \mathbf{D}_{t}=\left[p_{t}\quad p^{*}_{t}\quad \sum_{s=-\infty}^t y^{gap}_{s}\quad \sum_{s=-\infty}^ty^{gap*}_s,\sum_{s=-\infty}^t\pi_{s}\quad \sum_{s=-\infty}^t\pi^{*}_{s}\right]'.$

By definition, $ z_{t}=s_t-p_{t}+p^{*}_{t}+\frac{b}{1-b}(\delta_{y}(y^{gap}_{t}-y^{gap*}_{t})+\delta_{\pi}(\pi_{t}-\pi^{*}_{t}))$ . This corresponds to $ \beta_{m,h}=[1\quad \frac{b}{1-b}\delta_y\quad \frac{b}{1-b}\delta_\pi]$ and $ \mathbf{X}_{m,t}=[q_t\quad y_t^{gap}-y_t^{gap*}\quad \pi_t-\pi_t^*]$ , where $ q_t=s_t-p_{t}+p^{*}_{t}$ is the real exchange rate. $ \beta_{m,h}$ and $ \mathbf{X}_{m,t}$ can be defined differently. For instance, $ \beta_{m,h}=1$ and $ \mathbf{X}_{m,t}=s_t-p_{t}+p^{*}_{t}+\frac{b}{1-b}(\delta_{y}(y^{gap}_{t}-y^{gap*}_{t})+\delta_{\pi}(\pi_{t}-\pi^{*}_{t}))$ . Our results do not change qualitatively under this alternative setup.

A.3  Model with Heterogeneous Taylor Rules

In the benchmark model, we assume that the Taylor rule coefficients are the same in the home and foreign countries. In this appendix, we relax the assumption of homogeneous Taylor rules in the benchmark model. It is straightforward to show in this case that the benchmark model changes to:

$\displaystyle s_{t+h}-s_t=\alpha_h+\beta_hz_t+\varepsilon_{t+h},$ (A.3.1)

where the deviation of the exchange rate from its equilibrium level is defined as:

$\displaystyle z_t=s_t-p_t+p_t^\ast+\frac{b}{1-b}\left[\delta_yy_t^{gap}-\delta_y^\ast y_t^{gap\ast}+\delta_\pi\pi_t-\delta_\pi^\ast\pi_t^\ast\right].$ (A.3.2)

According to equation (8), the matrix $ \mathbf{X}_{1,t}$ in equation (1) includes economic variables $ q_t\equiv s_t+p_t^\ast-p_t$, $ \delta_yy_t^{gap}-\delta_y^\ast y_t^{gap\ast}$, and $ \delta_\pi\pi_t-\delta_\pi^\ast\pi_t^\ast$.25We first estimate the Taylor rules in the home and foreign countries according to equations (2) and (3). Then $ q_t\equiv s_t+p_t^\ast-p_t$, $ \hat{\delta}_yy_t^{gap}-\hat{\delta}_y^\ast y_t^{gap\ast}$, and $ \hat{\delta}_\pi\pi_t-\hat{\delta}_\pi^\ast\pi_t^\ast$ are used in the long-horizon regressions and interval forecasts. The results are very similar to the benchmark model and reported in Table 7.


Footnotes

1.  We thank Menzie Chinn, Charles Engel, Bruce Hansen, Jesper Linde, Enrique Martinez-Garcia, Tanya Moldtsova, David Papell, Mark Wynne, and Ken West for invaluable discussions. We would also like to thank seminar participants at the Dallas Fed and the University of Houston for helpful comments. All views are those of the authors and do not necessarily reflect the views of the Federal Reserve Bank of Dallas, the Board of Governors or the Federal Reserve System. All GAUSS programs are available upon request. Return to text

2.  Email: [email protected] Address: Research Department, Federal Reserve Bank of Dallas, 2200 N. Pearl Street, Dallas, TX 75201 Phone: (214) 922-6471. Return to text

3.  Email: [email protected] Address: Board of Governors of the Federal Reserve System, 20th and C Streets, Washington, D.C. 20551 Phone: (202) 452-2556. Return to text

4.  Chinn and Meese (1995) and MacDonald and Taylor (1994) find similar results. However, the long-horizon exchange rate predictability in Mark (1995) has been challenged by Kilian (1999) and Berkowitz and Giorgianni (2001) in subsequent studies. Return to text

5.  For brevity, we omit RS and simply say forecast intervals when we believe that it causes no confusion. Return to text

6.  The coefficients on lagged interest rates in the home and foreign countries can take different values in Molodtsova and Papell (2009). Return to text

7.  We also tried the random walk with a drift. It does not change our results. Return to text

8.  Clarida, Gali, and Gertler (1998) find empirical support for forward-looking Taylor rules. Forward-looking Taylor rules are ruled out because they require forecasts of predictors, which creates additional complications in out-of-sample forecasting. Return to text

9.  See appendix for more detail. While the long-horizon regression format of the benchmark Taylor model is derived directly from the underlying Taylor rule model, this is not the case for the models with interest rate smoothing (models 3 and 4). Molodtsova and Papell (2009) only consider the short-horizon regression for the Taylor rule models. We include long-horizon regressions of these models only for the purpose of comparison. Return to text

10.  We also tried the case of $ \mathbf{X}_{1,t}=z_{t}$. Our results do not change qualitatively. Return to text

11.  We thank the authors for the data, which we downloaded from David Papell's website. For the exact line numbers and sources of the data, see the data appendix of Molodtsova and Papell (2009). Return to text

12.  We choose $ b$ using the method of Hall, Wolff, and Yao (1999). Return to text

13.  It is consistent in the sense of convergence in probability as the estimation sample size goes to infinity. Return to text

14.  While RS intervals remedy mis-specifications asymptotically, it does not guarantee such corrections in a given finite sample. Return to text

15.  We use Newey and West (1987) for our empirical work, with a window width of 12. Return to text

16.  Center here means the half way point between the upper and lower bound for a given interval. Return to text

17.  These nine exchange rates are the Danish Kroner, the French Franc, the Deutschmark, the Japanese Yen, the Dutch Guilder, the Portuguese Escudo, the Swiss Franc, and the British pound. Similar results hold at other horizons. Return to text

18.  When comparing the intervals for $ S_{\tau+h} - S_{\tau}$, the random walk model builds the forecast interval around 0, while economic model $ m$ builds it around $ \widehat{\beta} ^{^{\prime}}_{m,h}\mathbf{X}_{m,\tau}$ Return to text

19.  Results are available upon request. Return to text

20.  The only exception is Portugal, where only 192 data points were available. In this case, we choose R = 120. Return to text

21.  See Appendix A.3 for details. Return to text

22.  See Wu (2009) for more discussion. Return to text

23.  Figures in other countries show similar patterns. Results are available upon request. Return to text

24.  To incorporate I(0) economic variables, $ \mathbf{D}_{t}$ contains the levels of I(1) variables and the summation of I(0) variables from negative infinity to time $ t$Return to text

25.  Another option to incorporate heterogenous Taylor rules is to include $ q_t$, $ y_t^{gap}$, $ y_t^{gap\ast}$, $ \pi_t$, and $ \pi_t^\ast$ in $ \mathbf{X}_{1,t}$. For instance, see Moldtsova and Papell (2009). However, increasing the number of regressors may cause the "curse of dimensionality" problem for our semiparametric method. To be comparable to our benchmark model, we define $ \mathbf{X}_{1,t}$ here such that the number of regressors is the same as in the benchmark model. Return to text


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