Ivan Paya

Nonlinear Purchasing Power Parity under the Gold Standard

Hegwood and Papell (2002) conclude on the basis of analysis in a linear framework that long-run purchasing power parity (PPP) does not hold for 16 real exchange rate series, which were analyzed in Diebold, Husted, and Rush (1991) for the period 1792–1913 under the Gold Standard. Rather, PPP deviations are mean-reverting to a changing equilibrium—a quasi PPP (QPPP) theory. We analyze the real exchange rate adjustment mechanism for their data set assuming a nonlinear adjustment process allowing for both a constant and a mean shifting equilibrium. Our results confirm that real exchange rates at that time were stationary, symmetric, nonlinear processes that revert to a nonconstant equilibrium rate. Speeds of adjustment were much quicker when breaks were allowed.

Linkages between Shanghai and Hong Kong stock indices

This article examines the dynamics of the linkages between Shanghai and Hong Kong stock indices. While the volatility linkage is analysed by a Multivariate Generalized Autoregressive Conditional Heteroscedasticity (MVGARCH) framework, the dependence of returns is examined by a copula approach. Eight different copula functions are applied in this study including two time-varying ones which capture the dynamics of the linkage. The result shows significant tail dependence of the returns in the two markets.

On the relationship between nominal exchange rates and domestic and foreign prices

A number of authors have found significant cointegrating relationships between spot exchange rates and domestic and foreign price levels for the major currencies where the magnitude of the coefficients makes economic interpretation of PPP cumbersome. Using theoretically well motivated nonlinear models for ‘artifitially’ created real exchange rates, this paper investigates the properties of two alternative cointegration procedures, namely the Johansen and Saikkonen methodologies. The latter procedure appears to outperform the former one in terms of finding the ‘true’ cointegrating coefficients. The new weights obtained with the Saikkonen method are then used to estimate non-linear ESTAR model for the real exchange rate. The ‘new’ real exchange rates exhibit, in most cases, much lower half-life shocks than the ones predicted by the Rogoff (1996) puzzle.

Specifying Smooth Transition Regression Models in the Presence of Conditional Heteroskedasticity of Unknown Form

The specification of Smooth Transition Regression models consists of a sequence of tests, which are typically based on the assumption of i.i.d. errors. In this paper we examine the impact of conditional heteroskedasticity and investigate the performance of several heteroskedasticity robust versions. Simulation evidence indicates that conventional tests can frequently result in finding spurious nonlinearity. Conversely, when the true process is nonlinear in mean, the tests appear to have low size adjusted power and can lead to the selection of misspecified models. The above deficiencies also hold for tests based on Heteroskedasticity Consistent Covariance Matrix Estimators but not for the Fixed Design Wild Bootstrap. We highlight the importance of robust inference through empirical applications.

Higher-Order Risk Preferences, Constant Relative Risk Aversion and the Optimal Portfolio Allocation

We derive the conditions for the optimal portfolio choice within a constant relative risk aversion type of utility function considering alternative probability distributions that are able to capture the asymmetric and leptokurtic features of asset returns. We illustrate the role —beyond risk aversion— played by higher-order moments in the optimal decision to form a portfolio of risky assets. In particular, we show that higher-order risk attitudes such as prudence and temperance associated with the third and fourth moments of the distribution define different optimal portfolios than those constrained under risk aversion.

THE PROCESS FOLLOWED BY PPP DATA. ON THE PROPERTIES OF LINEARITY TESTS

Recent research has reported the lack of correct size in stationarity test for PPP deviations within a linear framework. However, theoretically well motivated non-linear models, such as the ESTAR, appear to parsimoniously fit the PPP data and provide an explanation for the PPP ‘puzzle’. Employing Monte Carlo experiments the size and power of the non-linear tests are analysed against a variety of nonstationary hypotheses. Aslo the ESTAR model is fitted to data from high inflation economies. The results provide further support for ESTAR specification.

Term spread and real economic activity in Korea: was the crisis predictable?

This paper has three objectives. First, it examines the link between the term spread (difference between long-term and short-term rate of interest) and GDP growth in the Korean economy for the period 1980–1999. Second, it tests for the independent information content of the term spread by including current and expected monetary policy indicators. Third, it explores the usefulness of the spread as a leading indicator of recessions and poses the question, was the crisis of 1997–1998 predictable?

TESTING FOR SPECULATIVE BUBBLES USING SPOT AND FORWARD PRICES: TESTING FOR SPECULATIVE BUBBLES USING SPOT AND FORWARD PRICES

The probabilistic structure of periodically collapsing bubbles creates a gap between future spot and forward (or futures) asset prices in small samples. By exploiting this fact, we use two econometric methods, namely, the recursive unit root method of Phillips, Shi, and Yu (2015a,b) and the rolling regression method of Fama (1984), for detecting bubbles. Both methods do not rely on a particular model of asset price determination, they are robust to an explosive root in the process for market fundamentals, and are accompanied by a date-stamping strategy. By applying these methods to the German mark-US dollar and British pound-US dollar exchange rates, we provide evidence in favor of speculative bubbles in the foreign exchange market during the interwar German hyperinflation, but not during the recent floating-rate period. A further application to the S&P 500 index supports the existence of speculative bubbles in the US equity market.

Monitoring Housing Markets for Episodes of Exuberance: An Application of the Phillips Et Al. (2012, 2013) GSADF Test on the Dallas Fed International House Price Database

The detection of explosive behavior in house prices and the implementation of early warning diagnosis tests are of great importance for policy-making. This paper applies the GSADF test developed by Phillips et al. (2012) and Phillips et al. (2013), a novel procedure for testing, detection and date-stamping of explosive behavior, to the data from the Dallas Fed International House Price Database documented in Mack and Martinez-Garcia (2011). We discuss the use of the GSADF test to monitor international housing markets. We assess the international boom and bust cycle experienced during the past 15 years through this lens — with special attention to the United States, the United Kingdom, and Spain. Our empirical results suggest that these three countries experienced a period of exuberance in housing prices during the late 90s and the first half of the 2000s that cannot be attributed solely to the behavior of fundamentals. Looking at all 22 countries covered in the International House Price Database, we detect a pattern of synchronized explosive behavior during the last international house boom-bust episode not seen before.

Nonlinear causality tests and multivariate conditional heteroskedasticity:a simulation study

Abstract This paper assesses the performance of linear and nonlinear causality tests in the presence of multivariate conditional heteroskedasticity, exogenous volatility regressors, and additive volatility outliers. Monte Carlo simulations show that tests based on the least squares covariance matrix estimator can frequently lead to finding spurious Granger causality. The degree of oversizing tends to increase with the sample size and is substantially larger for the nonlinear test. On the other hand, heteroskedasticity-robust tests which are based on the fixed design wild bootstrap perform adequately in terms of size and power. Consequently, reliable causality in mean tests can be conducted without the need to specify a conditional variance function. As an empirical application, we re-examine the return-volume relationship.