Deviations from uncovered interest parity in Malaysia

This paper applies the Switching ARCH (SWARCH) model of Hamilton and Susmel (1994) to investigate the dynamics of deviations from Uncovered Interest Parity (UIP) for Malaysia for the sample period 1978-2002. In particular, the deviations (or the risk premium) are modelled as a time series subject to discrete regime shifts between two possible states, “high volatility” and “low volatility”. We find that the SWARCH model provides a better description of the data and implies a much lower degree of volatility persistence than conventional ARCH models. Overall, the SWARCH model provides a clearer picture of how the UIP deviations have evolved over time and how the changes in the volatility of the deviations have coincided with major changes in financial liberalisation in Malaysia. This adds credibility to the hypothesis that the shifts are not statistical artefacts but indeed reflect real economic changes.