Elias Tzavalis

Explaining the Failures of the Term Spread Models of the Rational Expectations Hypothesis of the Term Structure

Contrary to the predictions of the rational expectations hypothesis of the term structure of interest rates, empirical evidence suggests that the term spread between long and short rates fails to forecast future movements of long-term rates although its forecasts of future short-term rates are in the correct direction. In this paper, the authors show that this puzzling behavior of the term spread alone can be explained by a time-varying term premium that is correlated with the term spread. Once this is accounted for, neither expression of the expectations hypothesis is against the predictions of the theory. Copyright 1997 by Ohio State University Press.

Testing for Unit Roots in Short Dynamic Panels with Serially Correlated and Heteroscedastic Disturbance Terms

In this paper we introduce fixed-T unit root tests for panel data models with serially correlated and heteroscedastic disturbance terms. The tests are based on pooled least squares estimators for the autoregressive coefficient of the AR(1) panel model adjusted for their inconsistency. The proposed test statistics have normal limiting distributions when the cross-section dimension of the panel grows large, provided a condition involving the 4+δ-th order moments of the first differences of the data is satisfied. Monte Carlo evidence suggests that the tests have empirical size close to the nominal level and considerable power, even for MA(1) disturbance terms which exhibit strong negative autocorrelation.

Is the Currency Risk Priced in Equity Markets

In this paper we investigate whether the currency risk is priced in international stock markets. We suggest a parsimonious version of the international capital asset pricing model with an EGARCH-M(1,1) specification of the second moments dynamics of stock and currency returns, assuming that the latter follow a multivariate t-distribution. This specification allows for asymmetric responses of volatility to stock and currency news, including leverage effects. Our results suggest that the currency risk is priced in international stock markets, once asymmetries in volatility are taken into account. The currency premium is found to be significant on both statistic and economic grounds. We find that a dynamic portfolio strategy that hedges against currency changes provides higher returns (as a reward for currency premium) than a strategy which ignores them.

A Bayesian Analysis of Unit Roots and Structural Breaks in the Level and the Error Variance of Autoregressive Models of economic series

In this paper, a Bayesian approach is suggested to compare unit root models with stationary models when both the level and the error variance are subject to structural changes (known as breaks) of an unknown date. The paper utilizes analytic and Monte Carlo integration techniques for calculating the marginal likelihood of the models under consideration, in order to compute the posterior model probabilities. The performance of the method is assessed by simulation experiments. Some empirical applications of the method are conducted with the aim to investigate if it can detect structural breaks in financial series, with changes in the error variance.

A Bayesian Analysis of Unit Roots in Panel Data Models with Cross-Sectional Dependence

In this paper a Bayesian approach to unit root testing for panel data models is proposed based on the comparison of stationary autoregressive models with and without individual determinist trends, with their counterpart models with unit autoregressive roots. This is done under cross-sectional dependence among the units of the panel. Simulation experiments are conducted with the aim to assess the performance of the suggested inferential procedure, as well as to investigate if the Bayesian model comparison approach can distinguish unit root models from stationary autoregressive models under or without cross-section dependence. The approach is applied to real GDP data for a panel of G7.