Olan T. Henry

The Effect of Asymmetries on Optimal Hedge Ratios

There is widespread evidence that the volatility of stock returns displays an asymmetric response to good and bad news. This article considers the impact of asymmetry on time-varying hedges for financial futures. An asymmetric model that allows forecasts of cash and futures return volatility to respond differently to positive and negative return innovations gives superior in-sample hedging performance. However, the simpler symmetric model is not inferior in a hold-out sample. A method for evaluating the models in a modern risk-management framework is presented, highlighting the importance of allowing optimal hedge ratios to be both time-varying and asymmetric.

Does the Australian dollar real exchange rate display mean reversion

Non-stationarity of the real exchange rate is inconsistent with purchasing power parity as a long run equilibrium. This paper applies parametric and non-parametric techniques to data from a trade weighted index to analyse the time series properties of Australias real exchange rate. In contrast to recent work by Olekalns amd Wilkins (1998) we conclude that shocks to the real exchange rate are infinitely persistent.

Linear and Non-Linear Transmission of Equity Return Volatility: Evidence From the US, Japan, and Australia

This paper examines the transmission of shocks between the US, Japanese and Australian equity markets. Tests for the existence of linear and non-linear transmission of volatility across the markets are performed using parametric and non-parametric techniques.

The Effect of Recessions on the Relationship Between Output Variability and Growth

This paper investigates the relationship between output volatility and growth using post-war real GDP data for the United States. We expand on recent research by Beaudry and Koop (1993) documenting the asymmetric effect of recessions on output growth. The results presented in this paper suggest that output volatility is highest when the economy is contracting. While we find that the economy expands most rapidly following a recession, this expansion is offset by the negative impact of output uncertainty.

Measuring the response of macroeconomic uncertainty to shocks

Recent research documents the importance of uncertainty in determining macroeconomic outcomes, but little is known about the transmission of uncertainty across such outcomes. This paper examines the response of uncertainty about inflation and output growth to shocks documenting statistically significant size and sign bias and spillover effects. Uncertainty about inflation is a determinant of output uncertainty, whereas higher growth volatility tends to raise inflation volatility. Both inflation and growth volatility respond asymmetrically to positive and negative shocks. Negative growth and inflation shocks lead to higher and more persistent uncertainty than shocks of equal magnitude but opposite sign.

Can portmanteau nonlinearity tests serve as general mis-specification tests?: Evidence from symmetric and asymmetric GARCH models

A number of recent papers have employed the BDS test as a general test for mis-specification for linear and nonlinear models. We show that for a particular class of conditionally heteroscedastic models, the BDS test is unable to detect a common mis-specification. Our results also demonstrate that specific rather than portmanteau diagnostics are required to detect neglected asymmetry in volatility. However for both classes of tests reasonable power is only obtained using very large sample sizes.

Exchange Rate Instability: A Threshold Autoregressive Approach

We fit a two-regime threshold autoregressive model to a trade weighted index of the Australian real exchange rate. We find strong evidence of a threshold in the real exchange rate, with the data being classified into two regimes. The timing of the first regime is consistent with events that would be expected to have led to pressure on the Australian exchange rate. However, there is no evidence to suggest that the Asian economic crisis led to the real exchange rate entering this regime. Copyright 2001 by The Economic Society of Australia.

The Impact of News on Measures of Undiversifiable Risk: Evidence from the UK Stock Market

Using UK equity index data, this paper considers the impact of news on time varying measures of beta, the usual measure of undiversifiable risk. The empirical model implies that beta depends on news about the market and news about the sector. The asymmetric response of beta to news about the market is consistent across all sectors considered. Recent research is divided as to whether abnormalities in equity returns arise from changes in expected returns in an efficient market or over-reactions to new information. The evidence in this paper suggests that such abnormalities may be due to changes in expected returns caused by time-variation and asymmetry in beta. Copyright 2002 by Blackwell Publishing Ltd

Asymmetric Conditional Volatility and Firm Size: Evidence from Australian Equity Portfolios

This paper examines the relationship betwen firm size and equity volatility for two portfolios of Australian equities. Univariate and multivariate asymmetric GARCH models are used to demonstrate that conditional volatility is related to firm size. There is strong evidence to suggest that the variance-covariance matrix of returns is time varying and asymetric.

Rational habit modification in consumption

This paper proposes an asymmetric model within which consumer credit facilitates both consumption smoothing and rational habit modification. The model is applied to US data using a GMM approach. The evidence suggests that new credit can predict short-run changes in consumption and has assisted consumers to become more forward-looking.